Dust removal from pyrolytic vapors at high temperatures is an obstacle to the industrialization of the coal pyrolysis process.In this work,a granular bed with expanded perlites as filtration media was designed and int...Dust removal from pyrolytic vapors at high temperatures is an obstacle to the industrialization of the coal pyrolysis process.In this work,a granular bed with expanded perlites as filtration media was designed and integrated into a 10 t·d^(–1)coal pyrolysis facility.The testing results showed that around 97.56%dust collection efficiency was achieved.As a result,dust content in tar was significantly lowered.The pressure drop of the granular bed maintained in the range of 356 Pa to 489 Pa.The dust size in the effluent after filtration exhibited a bimodal distribution,which was attributed to the heterogeneity of the dust components.The effects of filtration bed on pyrolytic product yields were also discussed.A modified filtration model based on the macroscopic phenomenological theory was proposed to describe the performance of the granular bed.The computation results were well agreed with the experimental data.展开更多
Many phenomena in nature and technology are associated with the filtration of suspensions and colloids in porous media. Two main types of particle deposition,namely, cake filtration at the inlet and deep bed filtratio...Many phenomena in nature and technology are associated with the filtration of suspensions and colloids in porous media. Two main types of particle deposition,namely, cake filtration at the inlet and deep bed filtration throughout the entire porous medium, are studied by different models. A unified approach for the transport and deposition of particles based on the deep bed filtration model is proposed. A variable suspension flow rate, proportional to the number of free pores at the inlet of the porous medium, is considered. To model cake filtration, this flow rate is introduced into the mass balance equation of deep bed filtration. For the cake filtration without deposit erosion,the suspension flow rate decreases to zero, and the suspension does not penetrate deep into the porous medium. In the case of the cake filtration with erosion, the suspension flow rate is nonzero, and the deposit is distributed throughout the entire porous medium. An exact solution is obtained for a constant filtration function. The method of characteristics is used to construct the asymptotics of the concentration front of suspended and retained particles for a filtration function in a general form. Explicit formulae are obtained for a linear filtration function. The properties of these solutions are studied in detail.展开更多
Investigating the characteristics and transformation of water-soluble carbonaceous matter in the cryosphere regions is important for understanding biogeochemical process in the earth system.Water-soluble carbonaceous ...Investigating the characteristics and transformation of water-soluble carbonaceous matter in the cryosphere regions is important for understanding biogeochemical process in the earth system.Water-soluble carbonaceous matter is a heterogeneous mixture of organic compounds that is soluble in aquatic environments.Despite its importance,we still lack systematic understanding for dissolved organic carbon(DOC)in several aspects including exact chemical composition and physical interactions with microorganisms,glacier meltwater.This review presents the chemical composition and physical properties of glacier DOC deposited through anthropogenic emission,terrestrial,and biogenic sources.We present the molecular composition of DOC and its effect over snow albedo and associated radiative forcings.Results indicate that DOC in snow/ice is made up of aromatic protein-like species,fulvic acid-like materials,and humic acid-like materials.Light-absorbing impurities in surface snow and glacier ice cause considerable albedo reduction and the associated radiative forcing is definitely positive.Water-soluble carbonaceous matter dominated the carbon transport in the high-altitude glacial area.Owing to prevailing global warming and projected increase in carbon emission,the glacial DOC is expected to release,which will have strong underlying impacts on cryosphere ecosystem.The results of this work have profound implications for better understanding the carbon cycle in high altitude cryosphere regions.A new compilation of globally distributed work is required,including large-scale measurements of glacial DOC over high-altitude cryosphere regions,to overcome and address the scientific challenges to constrain climate impacts of light-absorbing impurities related processes in Earth system and climate models.展开更多
The Southern Ocean is an important carbon sink pool and plays a critical role in the global carbon cycling.The Amundsen Sea was reported to be highly productive in inshore area in the Southern Ocean.In order to invest...The Southern Ocean is an important carbon sink pool and plays a critical role in the global carbon cycling.The Amundsen Sea was reported to be highly productive in inshore area in the Southern Ocean.In order to investigate the influence of transparent exopolymer particles(TEP)on the behavior of dissolved organic carbon(DOC)in this region,a comprehensive study was conducted,encompassing both open water areas and highly productive polynyas.It was found that microbial heterotrophic metabolism is the primary process responsible for the production of humic-like fluorescent components in the open ocean.The relationship between apparent oxygen utilization and the two humic-like components can be accurately described by a power-law function,with a conversion rate consistent with that observed globally.The presence of TEP was found to have little impact on this process.Additionally,the study revealed the accumulation of DOC at the sea surface in the Amundsen Sea Polynya,suggesting that TEP may play a critical role in this phenomenon.These findings contribute to a deeper understanding of the dynamics and surface accumulation of DOC in the Amundsen Sea Polynya,and provide valuable insights into the carbon cycle in this region.展开更多
As a river with more than 3000 reservoirs in its watershed,the Yellow River has been affected by dams not only on the sediment load,but also on the water quality.Water-sediment regulation scheme(WSRS),which has been c...As a river with more than 3000 reservoirs in its watershed,the Yellow River has been affected by dams not only on the sediment load,but also on the water quality.Water-sediment regulation scheme(WSRS),which has been carried out annually in the Yellow River since 2002,is a typical human activity affecting river water quality.Chromophoric dissolved organic matter(CDOM)in river is susceptible to changes in ecological and environmental conditions as well as human activities.Here,we report variations in dissolved organic carbon concentrations,compositions and sources of CDOM in time series samples in the lower Yellow River during WSRS.In addition,a parallel factor fluorescence analysis(PARAFAC)method is applied to identify different fluorescent components in water samples during WRSR,showing four major components including tryptophan-like component(C1),microbial humic-like component(C2),terrestrial humic-like component(C3)and tyrosine-like component(C4).In general,C1 increased after water regulation,while C2 and C3 increased after sediment regulation,indicating that the water and sediment released by the dam have different effects on CDOM compositions.Under the impacts of the dam,source of CDOM in the lower Yellow River is mainly autochthonous related to microbial activities,and is regulated by the terrestrial input during WSRS period.Sediment resuspension inhibits microbial activities and reduces the production of autochthonous CDOM.Overall,human activities especially WSRS,as exemplified here,significantly alter the quality and quantity of CDOM in the lower Yellow River,affecting CDOM dynamics and biogeochemical processes in the estuarine environment.展开更多
This study presents a significant contribution to the field of water quality assessment and sustainable water management practices. By evaluating the levels of total dissolved solids (TDS) in seawater intakes within A...This study presents a significant contribution to the field of water quality assessment and sustainable water management practices. By evaluating the levels of total dissolved solids (TDS) in seawater intakes within Al-Khobar desalination production system, the study addresses a crucial aspect of water treatment and environmental impact assessment. The findings provide valuable insights into the variations and trends of TDS levels across different phases of the system, highlighting the importance of monitoring and management strategies. The study provided both gravimetric total dissolved solids (TDS) and electrical conductivity (EC) measurements to analyze TDS calculation factor and evaluate measurement accuracy. Results revealed significant variations in TDS levels across the sampling locations, with phase-2 exhibiting higher levels and greater fluctuations. Phase-3 displayed similar trends but with lower TDS levels, while phase-4 showed slightly different behavior with higher average TDS levels. EC measurements demonstrated a strong correlation with TDS, providing a reliable estimation. However, additional methods such as gravimetric analysis should be employed to confirm TDS measurements. The findings contribute to understanding water quality in the Al-Khobar desalination system, aiding in monitoring, management, and decision-making processes for water treatment and environmental impact assessment. The study enhances the credibility of water quality assessments and supports sustainable water management practices.展开更多
This article examines the influence of seawater temperature and total dissolved solids (TDS) on reverse osmosis (RO) desalination in the Arabian Gulf region, with a focus on the impact of climate change. The study hig...This article examines the influence of seawater temperature and total dissolved solids (TDS) on reverse osmosis (RO) desalination in the Arabian Gulf region, with a focus on the impact of climate change. The study highlights the changes in seawater temperature and TDS levels over the years and discusses their effects on the efficiency and productivity of RO desalination plants. It emphasizes the importance of monitoring TDS levels and controlling seawater temperature to optimize water production. The article also suggests various solutions, including intensive pre-treatment, development of high-performance membranes, exploration of alternative water sources, and regulation of discharges into the Gulf, to ensure sustainable water supply in the face of rising TDS levels and seawater temperature. Further research and comprehensive monitoring are recommended to understand the implications of these findings and develop effective strategies for the management of marine resources in the Arabian Gulf.展开更多
Water quality deterioration took place during infiltration process. Quality of the source water, climate conditions and amounts of added water are the major role players of the differentiation measures. Treated wastew...Water quality deterioration took place during infiltration process. Quality of the source water, climate conditions and amounts of added water are the major role players of the differentiation measures. Treated wastewater, rainwater and fresh groundwater were described within this study. It was found that the rainwater has an aggressive behavior with a high ability to dissolve soil salts. The amounts of Total Dissolved Solids (TDS) increase with infiltration process. Electrical conductivity (EC) increased by 600%. Plotting the fresh groundwater to the same conditions and experiment reflects the ability of this water to dissolve soil salts and increases the TDS by increasing the EC by a percentage of around 200%;while applying lower quality of water, the percentage of the EC of the treated wastewater increases to about 230% for the depth of 20 cm, which indicates the accumulation of the salts within this part of the soil, which leads to the deterioration of the soil quality, and decreases to about 160% for a depth of 60 cm. This differentiation could be a result of low permeability soils which tend to accumulate salts as a result of evaporation and then increase the salinity in the topsoil. Dissolution and plant uptake in the infiltrated take of minerals save the soil’s water from evaporation and do not allow salts to concentrate in soils. Moreover, plant uptake of soil water chemicals causes a decrease in some salt concentrations such as NO3, PO4, K, Na, and Cl and may conserve others.展开更多
The primary purpose of this research is to evaluate the feasibility of dissolved air flotation(DAF) as pretreatment process for membrane modules in river water treatment.The performances of DAF in combination with an ...The primary purpose of this research is to evaluate the feasibility of dissolved air flotation(DAF) as pretreatment process for membrane modules in river water treatment.The performances of DAF in combination with an up-flow membrane biofilter(MBF) and a hollow-fiber ultrafiltration membrane(UFM) were investigated respectively.Removal efficiency of ultraviolet absorbance at 254 nm(UV254),ammonia nitrogen(NH3-N),particle counts and microbial index were measured for both systems.Results showed that DAF was a robust pretreatment process for floc particles separation despite of raw water quality fluctuations.For DAFUFM system,the monitoring data indicated bacteria breeding,nitrite accumulation in membrane vessel and the ammonia concentration of permeate water even exceeded regulatory limits.By contrast,DAF-MBF system was established via the introduction of multilayer filter media between DAF and curtain type ultrafiltration membrane.In MBF,the matured biological activated carbon(BAC) and zeolite particles guaranteed the efficient removal of both organic matters and ammonia.Moreover,the high dissolved oxygen levels in DAF effluent significantly improved bio-adsorption and degradation of pollutants in MBF.The retention of microorganisms by the membrane not only ensured a high concentration of biomass,but also eliminated the risk of microbes leaking out from MBF.In addition,compared with UFM,the curtain membrane exhibited obviously slower fouling development.These results suggested that the DAF-MBF system was more suitable for purifying raw waters seriously polluted by dissolved contaminants.展开更多
The performance of a disc tube (DT) methodology, originally designed for reverse osmosis (RO) in desalination, and applied here for ultrafiltration (UF) and nanofiltration (NF) of dissolved organic matter (DOM) in a s...The performance of a disc tube (DT) methodology, originally designed for reverse osmosis (RO) in desalination, and applied here for ultrafiltration (UF) and nanofiltration (NF) of dissolved organic matter (DOM) in a set of fresh (0 ppt), brackish (10 ppt) and saline (30 ppt) waters at low (1 - 2 mg/L), medium (5 - 6 mg/L) and high (10 - 12 mg/L) dissolved organic carbon (DOC) content is presented. The DT module allows for time efficient processing of large volumes of sample and can be operated with RO, NF and UF membranes. We examined the performance of a NF membrane with nominal molecular weight cut-off (MWCO) of 500 Da and UF membranes with MWCO of 1 kDa and 10 kDa. Throughout the experiments we monitored DOM in terms of DOC, UV-absorption coefficient ratios (E2/E3) and the specific UV-absorbance at 254 nm (SUVA254). Detailed protocols for operating the disc tube modules are proposed. The membranes can be efficiently cleaned to provide low carbon blanks ( mg/L). Calibration confirmed separation of high and low molecular weight standards into the retentate and permeate fractions, respectively. DOC mass balance of fractionated DOM samples showed good recoveries (123% ± 32% at 500 Da, 95% ± 12% at 1 kDa and 99% ± 11% at 10 kDa) (n = 9). The actual retention rates for 500 Da and 1 kDA were close to those reported by the manufacturer (~200 Da and ~3 kDa, respectively). However, the manufacturer’s rated 10 kDa membrane actually retained only DOM > 35 kDa. Salt addition (up to 30 ppt) caused a significant reduction in the amount of high molecular weight (HMW) compounds isolated in the 1 and 10 kDa retentates, due to coiling of macromolecules with increasing ionic strength. These findings underline the importance of stringent operating protocols and the salinity dependence of HMW retention.展开更多
Air-borne pollutants in particulate matter(PM)form,produced either physically during industrial processes or certain biological routes,have posed a great threat to human health.Particularly during the current COVID-19...Air-borne pollutants in particulate matter(PM)form,produced either physically during industrial processes or certain biological routes,have posed a great threat to human health.Particularly during the current COVID-19 pandemic,effective filtration of the virus is an urgent matter worldwide.In this review,we first introduce some fundamentals about PM,including its source and classification,filtration mechanisms,and evaluation parameters.Advanced filtration materials and their functions are then summarized,among which polymers and MOFs are discussed in detail together with their antibacterial performance.The discussion on the application is divided into end-of-pipe treatment and source control.Finally,we conclude this review with our prospective view on future research in this area.展开更多
A mass flow matching model(MFMM)was established for studying the stable status of solution electrospinning.The study of the solution droplet status at the needle tip focused on various combinations of applied voltages...A mass flow matching model(MFMM)was established for studying the stable status of solution electrospinning.The study of the solution droplet status at the needle tip focused on various combinations of applied voltages and injection rates to figure out their influence on steadily fabricating polyvinyl alcohol(PVA)nanofibers prepared from PVA spinning solutions with two different mass fractions(10%and 16%).The results revealed that during the stable electrospinning,the influence resulted from the change of the injection rate approximately canceled out the impact brought by adjusting the applied voltage,leading to almost the same morphology as that of the PVA nanofibers.And the mass fraction of PVA in the spinning solution dominated the structure and the diameter distribution of the electrospun nanofibers.Under stable electrospinning conditions,the composite membrane was produced by depositing PVA nanofibers on the polyethylene terephthalate(PET)nonwoven substrate for an air filtration test.Furthermore,the prepared composite membrane exhibited a high air filtration efficiency(99.97%)and a low pressure drop(120 Pa)for 300-500 nm neutralized polystyrene latex(PSL)aerosol particles,demonstrating its potential as an alternative for a variety of commercial applications in air filtration.展开更多
In general,malachite is recovered via sulfidization–xanthate flotation,although many unsatisfactory flotation indexes are frequently obtained as a result of the presence of associated calcite.This phenomenon occurs b...In general,malachite is recovered via sulfidization–xanthate flotation,although many unsatisfactory flotation indexes are frequently obtained as a result of the presence of associated calcite.This phenomenon occurs because the dissolved components of malachite and calcite affect the flotation behavior of both minerals.In this study,the effect of the dissolved components derived from malachite and calcite on the flotation behavior and surface characteristics of both minerals was investigated.Flotation tests indicated that malachite recovery decreased when the calcite supernatant was introduced,while the presence of the malachite supernatant increased the recovery of calcite.Dissolution and adsorption tests,along with zeta potential measurements,X-ray photoelectron spectroscopy,Fourier transform infrared spectrometry,and timeof-flight secondary ion mass spectrometry demonstrated that the Ca species in the calcite supernatant were adsorbed on the malachite surface,which hindered the interaction of Na2S with malachite,thereby resulting in the insufficient adsorption of sodium isoamyl xanthate(NaIX)on the surface of malachite.By contrast,the Cu species in the malachite supernatant were adsorbed on the calcite surface,and they provided active sites for the subsequent adsorption of Na_(2)S and NaIX.展开更多
AIM:To evaluate the trend of glaucoma internal filtration surgeries for inpatients between 2015 and 2021 at the Eye Hospital of Wenzhou Medical University.METHODS:A review of the medical records of inpatients who had ...AIM:To evaluate the trend of glaucoma internal filtration surgeries for inpatients between 2015 and 2021 at the Eye Hospital of Wenzhou Medical University.METHODS:A review of the medical records of inpatients who had been diagnosed with glaucoma and received antiglaucoma surgery between January 1,2015 and December 31,2021 was conducted.The glaucoma diagnosis in this study included primary open angle glaucoma,primary angleclosure glaucoma,secondary glaucoma,and paediatric glaucoma.The types of surgeries were categorised as internal filtration,external filtration,and cyclodestruction surgery based on the pathway of aqueous humor outflow.The trend of these glaucoma surgeries in the sample of patients with different types of glaucoma was then analysed.RESULTS:The number of patients hospitalised for glaucoma surgery increased yearly,from 752 in 2015 to 1373 in 2021,at the Eye Hospital of Wenzhou Medical University.Regarding the patients diagnosed with primary open angle glaucoma,internal filtration surgery increased from 27.40%of the sample to 54.40%of the sample,while external filtration surgery decreased from 71.50%to 44.20%between 2015 and 2021.For paediatric glaucoma,internal filtration surgery increased from 37.50%in 2015 to 88.20%in 2021.Whilst different types of surgeries were performed on the sample of patients with secondary glaucoma,the proportion of internal filtration surgery also showed an increase from 18.20%in 2015 to 40.90%in 2021.Meanwhile,internal filtration surgery in the patient sample with primary angle-closure glaucoma already accounted for over 70.00%in 2015,and showed a small increase by 2021.CONCLUSION:As surgical technology and surgical experience continue to elevate and improve,the range of glaucoma surgeries are correspondingly evolving.This study find that internal filtration surgeries accounted for an increasing proportion of treatments in the surgical management of glaucoma between 2015 and 2021.展开更多
Dissolved oxygen(DO)is one of most important factors which affect wide range physiologic features of including immune responses and intestinal bacterial community.However,the underlying mechanisms remain enigmatic.To ...Dissolved oxygen(DO)is one of most important factors which affect wide range physiologic features of including immune responses and intestinal bacterial community.However,the underlying mechanisms remain enigmatic.To address this question,the intestinal bacterial community compositions and the immune features of Atlantic salmon(Salmo salar)grown in recirculating aquaculture systems(RAS)were characterized.Fish were reared under different DO saturation levels,e.g.,200% saturation named high group(H),100%saturation named control group(CK),and 60%saturation named lower group(L).Large variations in the operational taxonomic units(OTUs)frequency distribution for the intestinal bacterial community of Atlantic salmon were observed.The intestinal bacterial community of all groups was dominated mainly by three phyla,e.g.,Proteobacteria.Firmicutes,and Bacteroidetes.Interestingly,Acinetobacter baumannii,an opportunistic pathogen of salmon was increased significantly in L group.We further monitored the immunity features of fish under different DO levels.The results show that leucocyte number,cortisol level,the expressions of interleukin-1β(IL-1β),Toll-like receptor 4(TLR4),and nucleotide-binding oligomerization domain like protein 2(NOD2)were higher at significant levels in the L group than those in the other two groups.TLR4 and NOD2 are usually related with the bacterial infections;therefore,it is reasonable to believe that the stronger immune responses observed in the L group might be related with the higher abundance of A.baumannii in the inte stine of Atlantic salmon.Overall,these findings demonstrated that low DO level may induce stronger immunity responses in Atlantic salmon.展开更多
Organic solvent nanofiltration(OSN)membranes have a great application prospect in organic solvent separation,but the development of OSN membranes is mainly restricted by trade-off between permeability and rejection ra...Organic solvent nanofiltration(OSN)membranes have a great application prospect in organic solvent separation,but the development of OSN membranes is mainly restricted by trade-off between permeability and rejection rate.In this work,a TA/Fe^(3+)polymer was introduced into polyetherimide(PEI)ultrafiltration membranes crosslinked with hexamethylene diamine as the intermediate layer,and OSN membranes with high separation performance and solvent permeability were obtained through interfacial polymerization and solvent activation.The interlayer with high surface hydrophilicity and a fixed pore structure controlled the adsorption/diffusion of the amine monomer during interfacial polymerization,forming a smooth(average surface roughness<5.5 nm),ultra-thin(separation layer thickness reduced from 150 to 16 nm)and dense surface structure polyamide(PA)layer.The PA-Fe^(3+)_3-HDA/PEI membrane retained more than 94%of methyl blue(BS)in 0.1 g·L^(-1)BS ethanol solution at 0.6 MPa,and the ethanol permeation reached 28.56 L^(-1)·m^(-2)·h^(-1).The average flux recovery ratio(FRR)of PA-Fe^(3+)_(3)-HDA/PEI membrane was found to be 84%,which has better fouling resistance than PA-HDA/PEI membrane,and it was found to have better stability performance through different solvent immersion experiments and continuous operation in 0.1 g·L^(-1)BS ethanol solution.Compared with thin-film composite nanofiltration membranes,the PA-Fe^(3+)_(3)-HDA/PEI membrane can be manufactured from an economical and environment-friendly method and overcomes the trade-off between permeability and rejection rate,showing great application potential in organic solvent separation systems.展开更多
Palmitoleic acid(POA)can be naturally found only in few oil seeds and has significant applications in pharmaceutical industry.Recently,the isolated oleaginous yeast Scheffersomyces segobiensis DSM 27193 was identified...Palmitoleic acid(POA)can be naturally found only in few oil seeds and has significant applications in pharmaceutical industry.Recently,the isolated oleaginous yeast Scheffersomyces segobiensis DSM 27193 was identified with high content of POA in its intracellular lipid(13.80%).In this study,process optimization focused on dissolved oxygen regulation to improve POA production was conducted.Dynamic agitation was found to do significant enhancement on POA-rich lipid production than aeration regulation.Under the best condition of 1000 r·min^(-1)of agitation and 1 vvm(airvolume/culture volume/min)of aeration,no ethanol was detected during the whole fermentation process,while a dry biomass concentration of 44.80 g·L^(-1)with 13.43 g·L^(-1)of lipid and 2.93 g·L^(-1)of POA was achieved.Transcription analysis revealed that the ethanol synthetic pathway was downregulated under the condition of high agitation,while the expression of the key enzymes responsible for lipid and POA accumulation were enhanced.展开更多
With the consumption of terrestrial metal resources,the exploitation of deep-sea polymetallic nodule minerals has been widely concerned around the world.Therefore,the environmental impact of deep-sea polymetallic nodu...With the consumption of terrestrial metal resources,the exploitation of deep-sea polymetallic nodule minerals has been widely concerned around the world.Therefore,the environmental impact of deep-sea polymetallic nodule mining cannot be ignored.However,duo to the lacks in stable and safe deep-sea(the depth>1000 m)vertical profile observation systems and consequently in long-term in-situ observation data,the sound speed and dissolved oxygen and the other water environment factors in the deposition areas of polymetallic nodules remains poorly understood.In this study,a deep-sea in-situ observation system was designed and deployed,and the water environment data of the polymetallic nodule deposition area were collected and analyzed.Result shows that the dissolved oxygen in the depth of 0–600 m was mainly affected by biological factors,while that in the area deeper than 600 m was affected by physical factors.The sound speed in the water body was mainly affected by temperature and pressure.At depths below 840 m,the sound speed is mainly controlled by temperature,and at depths between 840 m and 5700 m,the sound speed is mainly controlled by pressure.The correlations of sound speed vs.pressure and vs.temperature were regressed into equation.The resuspension of sediments rich in various metals may result in the reduction of dissolved oxygen and the improvement of redox potential.This environmental impact caused by a single sediment resuspension could last for 24 h or more.These findings enrich the understanding of the background value of the water environment in the polymetallic nodule deposition area.展开更多
Introduction: Our study focused on the evaluation of renal function in children with sickle cell disease compared to children without sickle cell disease at the pediatric emergency unit of the Donka National Hospital ...Introduction: Our study focused on the evaluation of renal function in children with sickle cell disease compared to children without sickle cell disease at the pediatric emergency unit of the Donka National Hospital and SOS Drepano-Guinea center. Patients and Methods: This was a cross-sectional descriptive and analytical study lasting 3 months (October 1 to December 31, 2020). Were included, all sickle cell and non-sickle cell children aged 0 to 15 received on an outpatient basis and had undergone an exploration of renal function (serum creatinine and urine dipstick). Results: We performed the urine dipstick and serum creatinine in 75 children, 45 of whom were sickle cell and 30 were not sickle cell. 27 of our patients or 36% had a reduction in GFR, among them 9 or 20% were sickle cell and 18 or 60% were not sickle cell. The most affected age group was 5 to 9 years in sickle cell (66.7%) and non-sickle cell (38.9%). In sickle cell patients, 9 cases (100%) had mild renal failure (IRL). Non-sickle cell patients, had 14 cases or 77.8% of IRL and 4 cases (22.2%) of moderate IR. Sickle cell disease and antibiotics which had the respective p-value (0.01);(0.02), were statistically significant with the onset of renal failure. Conclusion: Several factors including sickle cell anemia and antibiotics are believed to be involved in lowering GFR. It would be essential to detect early the children received in consultation.展开更多
Total dissolved nitrogen(TDN) is an important parameter for assessing the nutrient cycling and status of natural waters.The accurate determination of TDN in natural waters is essential for assessing its contents and d...Total dissolved nitrogen(TDN) is an important parameter for assessing the nutrient cycling and status of natural waters.The accurate determination of TDN in natural waters is essential for assessing its contents and distinguishing different forms of nitrogen in the water.The TDN in various systems has been largely documented,and the concentrations of TDN are usually obtained using high-temperature catalytic(HTC) or persulfate oxidation(PO).However,the accuracy of these methods and their suitability for all types of natural waters are still unclear.To explore both methods in-depth,assorted samples were tested,including eight solutions composed of nitrogen-containing compounds(3 dissolved inorganic nitrogen fractions:NO_(3)^(-),NO_(2)^(-)and NH_(4)^(+);5 organic compounds:EDTA-2Na,vitamin B1,vitamin B12,amino acids,and urea) and 105 natural waters which were collected from an open ocean(Northwest Pacific Ocean,28),a marginal sea(Yellow Sea,34),an estuary(Huanghe River mouth,31),rivers(Huanghe River,4;Licun River,4),and precipitations(4 samples).The results showed that heterocycles and molecular dimensions had certain effects on the oxidation efficiency of the PO method but had little effect on HTC.There was no significant difference between the two methods for natural waters,but HTC was more suitable for deep-sea samples with low TDN concentrations(less than 10 μmol/L) and low organic activity.Overall,HTC has a relatively simple measurement process,a high degree of automation,and low error.Therefore,HTC can be recommended to determine the TDN of samples in freshwater and seawater.展开更多
基金financial support from the National Key Research and Development Program of China(2018YFB0605003).
文摘Dust removal from pyrolytic vapors at high temperatures is an obstacle to the industrialization of the coal pyrolysis process.In this work,a granular bed with expanded perlites as filtration media was designed and integrated into a 10 t·d^(–1)coal pyrolysis facility.The testing results showed that around 97.56%dust collection efficiency was achieved.As a result,dust content in tar was significantly lowered.The pressure drop of the granular bed maintained in the range of 356 Pa to 489 Pa.The dust size in the effluent after filtration exhibited a bimodal distribution,which was attributed to the heterogeneity of the dust components.The effects of filtration bed on pyrolytic product yields were also discussed.A modified filtration model based on the macroscopic phenomenological theory was proposed to describe the performance of the granular bed.The computation results were well agreed with the experimental data.
文摘Many phenomena in nature and technology are associated with the filtration of suspensions and colloids in porous media. Two main types of particle deposition,namely, cake filtration at the inlet and deep bed filtration throughout the entire porous medium, are studied by different models. A unified approach for the transport and deposition of particles based on the deep bed filtration model is proposed. A variable suspension flow rate, proportional to the number of free pores at the inlet of the porous medium, is considered. To model cake filtration, this flow rate is introduced into the mass balance equation of deep bed filtration. For the cake filtration without deposit erosion,the suspension flow rate decreases to zero, and the suspension does not penetrate deep into the porous medium. In the case of the cake filtration with erosion, the suspension flow rate is nonzero, and the deposit is distributed throughout the entire porous medium. An exact solution is obtained for a constant filtration function. The method of characteristics is used to construct the asymptotics of the concentration front of suspended and retained particles for a filtration function in a general form. Explicit formulae are obtained for a linear filtration function. The properties of these solutions are studied in detail.
基金supported by the second Tibetan Plateau Scientific Expedition and Research Program(STEP)(2019QZKK0605)the National Natural Science Foundation of China(41971080)the support of Youth Innovation Promotion Association CAS(2021429)。
文摘Investigating the characteristics and transformation of water-soluble carbonaceous matter in the cryosphere regions is important for understanding biogeochemical process in the earth system.Water-soluble carbonaceous matter is a heterogeneous mixture of organic compounds that is soluble in aquatic environments.Despite its importance,we still lack systematic understanding for dissolved organic carbon(DOC)in several aspects including exact chemical composition and physical interactions with microorganisms,glacier meltwater.This review presents the chemical composition and physical properties of glacier DOC deposited through anthropogenic emission,terrestrial,and biogenic sources.We present the molecular composition of DOC and its effect over snow albedo and associated radiative forcings.Results indicate that DOC in snow/ice is made up of aromatic protein-like species,fulvic acid-like materials,and humic acid-like materials.Light-absorbing impurities in surface snow and glacier ice cause considerable albedo reduction and the associated radiative forcing is definitely positive.Water-soluble carbonaceous matter dominated the carbon transport in the high-altitude glacial area.Owing to prevailing global warming and projected increase in carbon emission,the glacial DOC is expected to release,which will have strong underlying impacts on cryosphere ecosystem.The results of this work have profound implications for better understanding the carbon cycle in high altitude cryosphere regions.A new compilation of globally distributed work is required,including large-scale measurements of glacial DOC over high-altitude cryosphere regions,to overcome and address the scientific challenges to constrain climate impacts of light-absorbing impurities related processes in Earth system and climate models.
基金funded by the National Natural Science Foundation of China(Grant nos.42276255 and 41976227)project“Impact and Response of Antarctic Seas to Climate Change,IRASCC 2020-2022”(Grant nos.01-01-02A and 02-02-05).
文摘The Southern Ocean is an important carbon sink pool and plays a critical role in the global carbon cycling.The Amundsen Sea was reported to be highly productive in inshore area in the Southern Ocean.In order to investigate the influence of transparent exopolymer particles(TEP)on the behavior of dissolved organic carbon(DOC)in this region,a comprehensive study was conducted,encompassing both open water areas and highly productive polynyas.It was found that microbial heterotrophic metabolism is the primary process responsible for the production of humic-like fluorescent components in the open ocean.The relationship between apparent oxygen utilization and the two humic-like components can be accurately described by a power-law function,with a conversion rate consistent with that observed globally.The presence of TEP was found to have little impact on this process.Additionally,the study revealed the accumulation of DOC at the sea surface in the Amundsen Sea Polynya,suggesting that TEP may play a critical role in this phenomenon.These findings contribute to a deeper understanding of the dynamics and surface accumulation of DOC in the Amundsen Sea Polynya,and provide valuable insights into the carbon cycle in this region.
基金supported by the National Natural Science Foundation of China(Nos.41876077,41376085).
文摘As a river with more than 3000 reservoirs in its watershed,the Yellow River has been affected by dams not only on the sediment load,but also on the water quality.Water-sediment regulation scheme(WSRS),which has been carried out annually in the Yellow River since 2002,is a typical human activity affecting river water quality.Chromophoric dissolved organic matter(CDOM)in river is susceptible to changes in ecological and environmental conditions as well as human activities.Here,we report variations in dissolved organic carbon concentrations,compositions and sources of CDOM in time series samples in the lower Yellow River during WSRS.In addition,a parallel factor fluorescence analysis(PARAFAC)method is applied to identify different fluorescent components in water samples during WRSR,showing four major components including tryptophan-like component(C1),microbial humic-like component(C2),terrestrial humic-like component(C3)and tyrosine-like component(C4).In general,C1 increased after water regulation,while C2 and C3 increased after sediment regulation,indicating that the water and sediment released by the dam have different effects on CDOM compositions.Under the impacts of the dam,source of CDOM in the lower Yellow River is mainly autochthonous related to microbial activities,and is regulated by the terrestrial input during WSRS period.Sediment resuspension inhibits microbial activities and reduces the production of autochthonous CDOM.Overall,human activities especially WSRS,as exemplified here,significantly alter the quality and quantity of CDOM in the lower Yellow River,affecting CDOM dynamics and biogeochemical processes in the estuarine environment.
文摘This study presents a significant contribution to the field of water quality assessment and sustainable water management practices. By evaluating the levels of total dissolved solids (TDS) in seawater intakes within Al-Khobar desalination production system, the study addresses a crucial aspect of water treatment and environmental impact assessment. The findings provide valuable insights into the variations and trends of TDS levels across different phases of the system, highlighting the importance of monitoring and management strategies. The study provided both gravimetric total dissolved solids (TDS) and electrical conductivity (EC) measurements to analyze TDS calculation factor and evaluate measurement accuracy. Results revealed significant variations in TDS levels across the sampling locations, with phase-2 exhibiting higher levels and greater fluctuations. Phase-3 displayed similar trends but with lower TDS levels, while phase-4 showed slightly different behavior with higher average TDS levels. EC measurements demonstrated a strong correlation with TDS, providing a reliable estimation. However, additional methods such as gravimetric analysis should be employed to confirm TDS measurements. The findings contribute to understanding water quality in the Al-Khobar desalination system, aiding in monitoring, management, and decision-making processes for water treatment and environmental impact assessment. The study enhances the credibility of water quality assessments and supports sustainable water management practices.
文摘This article examines the influence of seawater temperature and total dissolved solids (TDS) on reverse osmosis (RO) desalination in the Arabian Gulf region, with a focus on the impact of climate change. The study highlights the changes in seawater temperature and TDS levels over the years and discusses their effects on the efficiency and productivity of RO desalination plants. It emphasizes the importance of monitoring TDS levels and controlling seawater temperature to optimize water production. The article also suggests various solutions, including intensive pre-treatment, development of high-performance membranes, exploration of alternative water sources, and regulation of discharges into the Gulf, to ensure sustainable water supply in the face of rising TDS levels and seawater temperature. Further research and comprehensive monitoring are recommended to understand the implications of these findings and develop effective strategies for the management of marine resources in the Arabian Gulf.
文摘Water quality deterioration took place during infiltration process. Quality of the source water, climate conditions and amounts of added water are the major role players of the differentiation measures. Treated wastewater, rainwater and fresh groundwater were described within this study. It was found that the rainwater has an aggressive behavior with a high ability to dissolve soil salts. The amounts of Total Dissolved Solids (TDS) increase with infiltration process. Electrical conductivity (EC) increased by 600%. Plotting the fresh groundwater to the same conditions and experiment reflects the ability of this water to dissolve soil salts and increases the TDS by increasing the EC by a percentage of around 200%;while applying lower quality of water, the percentage of the EC of the treated wastewater increases to about 230% for the depth of 20 cm, which indicates the accumulation of the salts within this part of the soil, which leads to the deterioration of the soil quality, and decreases to about 160% for a depth of 60 cm. This differentiation could be a result of low permeability soils which tend to accumulate salts as a result of evaporation and then increase the salinity in the topsoil. Dissolution and plant uptake in the infiltrated take of minerals save the soil’s water from evaporation and do not allow salts to concentrate in soils. Moreover, plant uptake of soil water chemicals causes a decrease in some salt concentrations such as NO3, PO4, K, Na, and Cl and may conserve others.
基金Sponsored by the National High Technology Research and Development Program of China(Grant No.SS2012AA062902)the Science and Technology Department of Heilongjiang Province,China(Grant No.PS13H05)
文摘The primary purpose of this research is to evaluate the feasibility of dissolved air flotation(DAF) as pretreatment process for membrane modules in river water treatment.The performances of DAF in combination with an up-flow membrane biofilter(MBF) and a hollow-fiber ultrafiltration membrane(UFM) were investigated respectively.Removal efficiency of ultraviolet absorbance at 254 nm(UV254),ammonia nitrogen(NH3-N),particle counts and microbial index were measured for both systems.Results showed that DAF was a robust pretreatment process for floc particles separation despite of raw water quality fluctuations.For DAFUFM system,the monitoring data indicated bacteria breeding,nitrite accumulation in membrane vessel and the ammonia concentration of permeate water even exceeded regulatory limits.By contrast,DAF-MBF system was established via the introduction of multilayer filter media between DAF and curtain type ultrafiltration membrane.In MBF,the matured biological activated carbon(BAC) and zeolite particles guaranteed the efficient removal of both organic matters and ammonia.Moreover,the high dissolved oxygen levels in DAF effluent significantly improved bio-adsorption and degradation of pollutants in MBF.The retention of microorganisms by the membrane not only ensured a high concentration of biomass,but also eliminated the risk of microbes leaking out from MBF.In addition,compared with UFM,the curtain membrane exhibited obviously slower fouling development.These results suggested that the DAF-MBF system was more suitable for purifying raw waters seriously polluted by dissolved contaminants.
文摘The performance of a disc tube (DT) methodology, originally designed for reverse osmosis (RO) in desalination, and applied here for ultrafiltration (UF) and nanofiltration (NF) of dissolved organic matter (DOM) in a set of fresh (0 ppt), brackish (10 ppt) and saline (30 ppt) waters at low (1 - 2 mg/L), medium (5 - 6 mg/L) and high (10 - 12 mg/L) dissolved organic carbon (DOC) content is presented. The DT module allows for time efficient processing of large volumes of sample and can be operated with RO, NF and UF membranes. We examined the performance of a NF membrane with nominal molecular weight cut-off (MWCO) of 500 Da and UF membranes with MWCO of 1 kDa and 10 kDa. Throughout the experiments we monitored DOM in terms of DOC, UV-absorption coefficient ratios (E2/E3) and the specific UV-absorbance at 254 nm (SUVA254). Detailed protocols for operating the disc tube modules are proposed. The membranes can be efficiently cleaned to provide low carbon blanks ( mg/L). Calibration confirmed separation of high and low molecular weight standards into the retentate and permeate fractions, respectively. DOC mass balance of fractionated DOM samples showed good recoveries (123% ± 32% at 500 Da, 95% ± 12% at 1 kDa and 99% ± 11% at 10 kDa) (n = 9). The actual retention rates for 500 Da and 1 kDA were close to those reported by the manufacturer (~200 Da and ~3 kDa, respectively). However, the manufacturer’s rated 10 kDa membrane actually retained only DOM > 35 kDa. Salt addition (up to 30 ppt) caused a significant reduction in the amount of high molecular weight (HMW) compounds isolated in the 1 and 10 kDa retentates, due to coiling of macromolecules with increasing ionic strength. These findings underline the importance of stringent operating protocols and the salinity dependence of HMW retention.
基金National Natural Science Foundation of China (22075046,51972063)Natural Science Funds for Distinguished Young Scholar of Fujian Province (2020J06038)+2 种基金Natural Science Foundation of Fujian Province (2020J01514,2019J01652,2019J01256)China Postdoctoral Science Foundation (Pre-station) (Project No.2019TQ0061)111 Project (No.D17005).
文摘Air-borne pollutants in particulate matter(PM)form,produced either physically during industrial processes or certain biological routes,have posed a great threat to human health.Particularly during the current COVID-19 pandemic,effective filtration of the virus is an urgent matter worldwide.In this review,we first introduce some fundamentals about PM,including its source and classification,filtration mechanisms,and evaluation parameters.Advanced filtration materials and their functions are then summarized,among which polymers and MOFs are discussed in detail together with their antibacterial performance.The discussion on the application is divided into end-of-pipe treatment and source control.Finally,we conclude this review with our prospective view on future research in this area.
文摘A mass flow matching model(MFMM)was established for studying the stable status of solution electrospinning.The study of the solution droplet status at the needle tip focused on various combinations of applied voltages and injection rates to figure out their influence on steadily fabricating polyvinyl alcohol(PVA)nanofibers prepared from PVA spinning solutions with two different mass fractions(10%and 16%).The results revealed that during the stable electrospinning,the influence resulted from the change of the injection rate approximately canceled out the impact brought by adjusting the applied voltage,leading to almost the same morphology as that of the PVA nanofibers.And the mass fraction of PVA in the spinning solution dominated the structure and the diameter distribution of the electrospun nanofibers.Under stable electrospinning conditions,the composite membrane was produced by depositing PVA nanofibers on the polyethylene terephthalate(PET)nonwoven substrate for an air filtration test.Furthermore,the prepared composite membrane exhibited a high air filtration efficiency(99.97%)and a low pressure drop(120 Pa)for 300-500 nm neutralized polystyrene latex(PSL)aerosol particles,demonstrating its potential as an alternative for a variety of commercial applications in air filtration.
基金financially supported by Yunnan Fundamental Research Projects (No.202101BE070001-009)National Natural Science Foundation of China (No.51464029)。
文摘In general,malachite is recovered via sulfidization–xanthate flotation,although many unsatisfactory flotation indexes are frequently obtained as a result of the presence of associated calcite.This phenomenon occurs because the dissolved components of malachite and calcite affect the flotation behavior of both minerals.In this study,the effect of the dissolved components derived from malachite and calcite on the flotation behavior and surface characteristics of both minerals was investigated.Flotation tests indicated that malachite recovery decreased when the calcite supernatant was introduced,while the presence of the malachite supernatant increased the recovery of calcite.Dissolution and adsorption tests,along with zeta potential measurements,X-ray photoelectron spectroscopy,Fourier transform infrared spectrometry,and timeof-flight secondary ion mass spectrometry demonstrated that the Ca species in the calcite supernatant were adsorbed on the malachite surface,which hindered the interaction of Na2S with malachite,thereby resulting in the insufficient adsorption of sodium isoamyl xanthate(NaIX)on the surface of malachite.By contrast,the Cu species in the malachite supernatant were adsorbed on the calcite surface,and they provided active sites for the subsequent adsorption of Na_(2)S and NaIX.
基金Supported by the National Key Research and Development Project of China(No.2020YFC2008200)the Program for Zhejiang Leading Talent of S&T Innovation(No.2021R52012)+1 种基金Key Research and Development Projects of Zhejiang Province(No.2022C03112)the Zhejiang Provincial Program for the Cultivation of Leading Talents in Colleges and Universities(No.2020099)。
文摘AIM:To evaluate the trend of glaucoma internal filtration surgeries for inpatients between 2015 and 2021 at the Eye Hospital of Wenzhou Medical University.METHODS:A review of the medical records of inpatients who had been diagnosed with glaucoma and received antiglaucoma surgery between January 1,2015 and December 31,2021 was conducted.The glaucoma diagnosis in this study included primary open angle glaucoma,primary angleclosure glaucoma,secondary glaucoma,and paediatric glaucoma.The types of surgeries were categorised as internal filtration,external filtration,and cyclodestruction surgery based on the pathway of aqueous humor outflow.The trend of these glaucoma surgeries in the sample of patients with different types of glaucoma was then analysed.RESULTS:The number of patients hospitalised for glaucoma surgery increased yearly,from 752 in 2015 to 1373 in 2021,at the Eye Hospital of Wenzhou Medical University.Regarding the patients diagnosed with primary open angle glaucoma,internal filtration surgery increased from 27.40%of the sample to 54.40%of the sample,while external filtration surgery decreased from 71.50%to 44.20%between 2015 and 2021.For paediatric glaucoma,internal filtration surgery increased from 37.50%in 2015 to 88.20%in 2021.Whilst different types of surgeries were performed on the sample of patients with secondary glaucoma,the proportion of internal filtration surgery also showed an increase from 18.20%in 2015 to 40.90%in 2021.Meanwhile,internal filtration surgery in the patient sample with primary angle-closure glaucoma already accounted for over 70.00%in 2015,and showed a small increase by 2021.CONCLUSION:As surgical technology and surgical experience continue to elevate and improve,the range of glaucoma surgeries are correspondingly evolving.This study find that internal filtration surgeries accounted for an increasing proportion of treatments in the surgical management of glaucoma between 2015 and 2021.
基金Supported by the Shandong Province Key Research and Invention Program(No.2017CXGC010K)the China Agriculture Research System(No.CARS-47)+7 种基金the National Key Research and Development Program(No.2018YFD0901204)the National Infrastructure of Fishery Germplasm Resource(No.2019DKA30470)the Marine S&T Fund of Shandong Province for Pilot National Laboratory for Marine Science and Technology(Qingdao)(No.2018SDKJ0502-2)the National Natural Science Foundation of China(Nos.31872606,31572657,U1701233,31402283,31802319)the Department of Agriculture and Rural Areas of Guangdong Province(No.KA1911101)the Natural Science Foundation of Shandong Province(No.ZR2018BC053)the Agricultural Application Technology Innovation Project of Shandong Province in 2018/2019(No.SD2019YY011)the Shandong Province Major Scientific and Technological Innovation Projects(No.2019JZZY020710)。
文摘Dissolved oxygen(DO)is one of most important factors which affect wide range physiologic features of including immune responses and intestinal bacterial community.However,the underlying mechanisms remain enigmatic.To address this question,the intestinal bacterial community compositions and the immune features of Atlantic salmon(Salmo salar)grown in recirculating aquaculture systems(RAS)were characterized.Fish were reared under different DO saturation levels,e.g.,200% saturation named high group(H),100%saturation named control group(CK),and 60%saturation named lower group(L).Large variations in the operational taxonomic units(OTUs)frequency distribution for the intestinal bacterial community of Atlantic salmon were observed.The intestinal bacterial community of all groups was dominated mainly by three phyla,e.g.,Proteobacteria.Firmicutes,and Bacteroidetes.Interestingly,Acinetobacter baumannii,an opportunistic pathogen of salmon was increased significantly in L group.We further monitored the immunity features of fish under different DO levels.The results show that leucocyte number,cortisol level,the expressions of interleukin-1β(IL-1β),Toll-like receptor 4(TLR4),and nucleotide-binding oligomerization domain like protein 2(NOD2)were higher at significant levels in the L group than those in the other two groups.TLR4 and NOD2 are usually related with the bacterial infections;therefore,it is reasonable to believe that the stronger immune responses observed in the L group might be related with the higher abundance of A.baumannii in the inte stine of Atlantic salmon.Overall,these findings demonstrated that low DO level may induce stronger immunity responses in Atlantic salmon.
基金supported by grants from the National Natural Science Foundation of China (41662004)the Jiangxi Graduate Innovation Fund (YC2021-S557),China。
文摘Organic solvent nanofiltration(OSN)membranes have a great application prospect in organic solvent separation,but the development of OSN membranes is mainly restricted by trade-off between permeability and rejection rate.In this work,a TA/Fe^(3+)polymer was introduced into polyetherimide(PEI)ultrafiltration membranes crosslinked with hexamethylene diamine as the intermediate layer,and OSN membranes with high separation performance and solvent permeability were obtained through interfacial polymerization and solvent activation.The interlayer with high surface hydrophilicity and a fixed pore structure controlled the adsorption/diffusion of the amine monomer during interfacial polymerization,forming a smooth(average surface roughness<5.5 nm),ultra-thin(separation layer thickness reduced from 150 to 16 nm)and dense surface structure polyamide(PA)layer.The PA-Fe^(3+)_3-HDA/PEI membrane retained more than 94%of methyl blue(BS)in 0.1 g·L^(-1)BS ethanol solution at 0.6 MPa,and the ethanol permeation reached 28.56 L^(-1)·m^(-2)·h^(-1).The average flux recovery ratio(FRR)of PA-Fe^(3+)_(3)-HDA/PEI membrane was found to be 84%,which has better fouling resistance than PA-HDA/PEI membrane,and it was found to have better stability performance through different solvent immersion experiments and continuous operation in 0.1 g·L^(-1)BS ethanol solution.Compared with thin-film composite nanofiltration membranes,the PA-Fe^(3+)_(3)-HDA/PEI membrane can be manufactured from an economical and environment-friendly method and overcomes the trade-off between permeability and rejection rate,showing great application potential in organic solvent separation systems.
基金supported by the National Key Research & Development Program of China (2021YFC2101500, 2018YFA0902200)National Natural Science Foundation of China (22008115, 21978130)+4 种基金Jiangsu Province Natural Science Foundation for Youths (SBK2020044721)Jiangsu Provincial Agricultural Science and Technology Independent Innovation Fund Project (CX(21)3120)Jiangsu Planned Projects for Postdoctoral Research Funds (2021K085A)China Postdoctoral Science Foundation (2020M671467)Postdoctoral Research Funding Program of Jiangsu Province (2021K085A)
文摘Palmitoleic acid(POA)can be naturally found only in few oil seeds and has significant applications in pharmaceutical industry.Recently,the isolated oleaginous yeast Scheffersomyces segobiensis DSM 27193 was identified with high content of POA in its intracellular lipid(13.80%).In this study,process optimization focused on dissolved oxygen regulation to improve POA production was conducted.Dynamic agitation was found to do significant enhancement on POA-rich lipid production than aeration regulation.Under the best condition of 1000 r·min^(-1)of agitation and 1 vvm(airvolume/culture volume/min)of aeration,no ethanol was detected during the whole fermentation process,while a dry biomass concentration of 44.80 g·L^(-1)with 13.43 g·L^(-1)of lipid and 2.93 g·L^(-1)of POA was achieved.Transcription analysis revealed that the ethanol synthetic pathway was downregulated under the condition of high agitation,while the expression of the key enzymes responsible for lipid and POA accumulation were enhanced.
基金Supported by the National Natural Science Foundation of China(No.42107157)the Laboratory for Marine Geology,Qingdao National Laboratory for Marine Science and Technology(No.MGQNLM-KF202101)+1 种基金the Fundamental Research Funds for the Central Universities,SCUT(No.21CX06016A)the Harbin Engineering University at Qingdao(No.2022-SXZN-CXJJ-04-06+01)。
文摘With the consumption of terrestrial metal resources,the exploitation of deep-sea polymetallic nodule minerals has been widely concerned around the world.Therefore,the environmental impact of deep-sea polymetallic nodule mining cannot be ignored.However,duo to the lacks in stable and safe deep-sea(the depth>1000 m)vertical profile observation systems and consequently in long-term in-situ observation data,the sound speed and dissolved oxygen and the other water environment factors in the deposition areas of polymetallic nodules remains poorly understood.In this study,a deep-sea in-situ observation system was designed and deployed,and the water environment data of the polymetallic nodule deposition area were collected and analyzed.Result shows that the dissolved oxygen in the depth of 0–600 m was mainly affected by biological factors,while that in the area deeper than 600 m was affected by physical factors.The sound speed in the water body was mainly affected by temperature and pressure.At depths below 840 m,the sound speed is mainly controlled by temperature,and at depths between 840 m and 5700 m,the sound speed is mainly controlled by pressure.The correlations of sound speed vs.pressure and vs.temperature were regressed into equation.The resuspension of sediments rich in various metals may result in the reduction of dissolved oxygen and the improvement of redox potential.This environmental impact caused by a single sediment resuspension could last for 24 h or more.These findings enrich the understanding of the background value of the water environment in the polymetallic nodule deposition area.
文摘Introduction: Our study focused on the evaluation of renal function in children with sickle cell disease compared to children without sickle cell disease at the pediatric emergency unit of the Donka National Hospital and SOS Drepano-Guinea center. Patients and Methods: This was a cross-sectional descriptive and analytical study lasting 3 months (October 1 to December 31, 2020). Were included, all sickle cell and non-sickle cell children aged 0 to 15 received on an outpatient basis and had undergone an exploration of renal function (serum creatinine and urine dipstick). Results: We performed the urine dipstick and serum creatinine in 75 children, 45 of whom were sickle cell and 30 were not sickle cell. 27 of our patients or 36% had a reduction in GFR, among them 9 or 20% were sickle cell and 18 or 60% were not sickle cell. The most affected age group was 5 to 9 years in sickle cell (66.7%) and non-sickle cell (38.9%). In sickle cell patients, 9 cases (100%) had mild renal failure (IRL). Non-sickle cell patients, had 14 cases or 77.8% of IRL and 4 cases (22.2%) of moderate IR. Sickle cell disease and antibiotics which had the respective p-value (0.01);(0.02), were statistically significant with the onset of renal failure. Conclusion: Several factors including sickle cell anemia and antibiotics are believed to be involved in lowering GFR. It would be essential to detect early the children received in consultation.
基金The National Key Research and Development Project of China under contract No.2019YFC1407802the Fund of State Environmental Protection Key Laboratory of Coastal Ecosystem under contract No.202112+3 种基金the Open Fund of Key Laboratory of Marine Ecological Environment Science and EngineeringMinistry of Natural Resources under contract No.MESE-2019-06the National Natural Science Foundation of China under contract No.41876078the Shandong Provincial Natural Science Foundation of China under contract No.ZR2018MD016。
文摘Total dissolved nitrogen(TDN) is an important parameter for assessing the nutrient cycling and status of natural waters.The accurate determination of TDN in natural waters is essential for assessing its contents and distinguishing different forms of nitrogen in the water.The TDN in various systems has been largely documented,and the concentrations of TDN are usually obtained using high-temperature catalytic(HTC) or persulfate oxidation(PO).However,the accuracy of these methods and their suitability for all types of natural waters are still unclear.To explore both methods in-depth,assorted samples were tested,including eight solutions composed of nitrogen-containing compounds(3 dissolved inorganic nitrogen fractions:NO_(3)^(-),NO_(2)^(-)and NH_(4)^(+);5 organic compounds:EDTA-2Na,vitamin B1,vitamin B12,amino acids,and urea) and 105 natural waters which were collected from an open ocean(Northwest Pacific Ocean,28),a marginal sea(Yellow Sea,34),an estuary(Huanghe River mouth,31),rivers(Huanghe River,4;Licun River,4),and precipitations(4 samples).The results showed that heterocycles and molecular dimensions had certain effects on the oxidation efficiency of the PO method but had little effect on HTC.There was no significant difference between the two methods for natural waters,but HTC was more suitable for deep-sea samples with low TDN concentrations(less than 10 μmol/L) and low organic activity.Overall,HTC has a relatively simple measurement process,a high degree of automation,and low error.Therefore,HTC can be recommended to determine the TDN of samples in freshwater and seawater.
