Although the immunomodulatory activity of bamboo vinegar and charcoal powder(BVC)has been increasingly documented in domestic animals,the use of BVC as immunostimulant in fi sh aquaculture awaits verifi cation.In the ...Although the immunomodulatory activity of bamboo vinegar and charcoal powder(BVC)has been increasingly documented in domestic animals,the use of BVC as immunostimulant in fi sh aquaculture awaits verifi cation.In the present study,the immunostimulatory impacts of dietary BVC intake were investigated in an important aquaculture fi sh species,the African catfi sh Clarias gariepinus.Results show that the pathogen resistance of African catfi sh was signifi cantly improved by dietary BVC intake at the tested levels(0.5%-2%),as indicated by higher survival rates(approximately 1.52-1.85 times that without BVC supplementation)upon intraperitoneally injection of bacterial pathogen Aeromonas hydrophila.In addition,both the count and phagocytic activity of blood cells were signifi cantly up-regulated by a 45-day dietary supplementation of BVC.Moreover,compared to that of the control,fi sh individuals fed BVC containing diets exhibited signifi cant higher activities of superoxide dismutase(SOD),myeloperoxidase(MPO),and lysozyme(LYZ).The content of immunoglobulin M(IgM)in serum of African catfi sh was also induced by dietary BVC supplementation.Furthermore,the expression levels of interleukin-8(IL-8),toll-like receptor 1 and 5(TLR1 and TLR5),myeloid diff erentiation factor 88(MyD88),and nuclear factor kappa B(NFκB)in the head kidney were signifi cantly up-regulated.Our fi ndings indicate BVC could be an eff ective immunostimulant in teleost species,which may enhance fi sh immunity through improving hematic parameters,activating bioactive humoral molecules,and up-regulating immune related molecular pathways.展开更多
Thermal stability of lysozyme adsorbed on biomass charcoal powder (BCP), which was prepared from plant biomass wastes such as dumped adzuki bean, bamboo, and wood by pyrolysis without combustion under nitrogen atmosph...Thermal stability of lysozyme adsorbed on biomass charcoal powder (BCP), which was prepared from plant biomass wastes such as dumped adzuki bean, bamboo, and wood by pyrolysis without combustion under nitrogen atmosphere and comminution with a jet mill, was examined. Adsorbing lysozyme on BCP could sufficiently prevent proteins from denaturing and aggregating in an aqueous solution at high temperatures, and enhanced the refolding of thermally denatured proteins by cooling treatment. The remaining activities of lysozyme adsorbed on BCP of adzuki bean exhibited 51% by cooling treatment after the heat treatment at 90?C for 30 min, although that of native lysozyme was almost lost under the same experimental conditions. The thermostabilization effect of BCP on the remaining activity of adsorbed lysozyme was markedly dependent upon the kind of plant biomass wastes.展开更多
The study on the evaporation kinetics of zinc and lead in the pellets made of Zn-Pbbearing dust mixed with carbon,in nitrogen atmosphere at the temperature range between 1 100 ℃and 1 300 ℃,shows that the reduction t...The study on the evaporation kinetics of zinc and lead in the pellets made of Zn-Pbbearing dust mixed with carbon,in nitrogen atmosphere at the temperature range between 1 100 ℃and 1 300 ℃,shows that the reduction temperature has a significant effect on the evaporation rates of zinc and lead and that both the particle size of coal powder and the extra carbon content have no effect on the evaporation rates.The obtained activation energies for the evaporation of zinc and lead are 79.42 kJ/mol and 88.74 kJ/mol respectively.The evaporation rate of zinc is controlled by the reaction between zinc oxide and CO while that of lead is controlled by lead volatilization and the diffusion of gaseous lead through gas boundary layer covering the surface of liquid lead.展开更多
Biomass charcoal powder (BCP) was used as a carrier matrix for immobilization of chicken egg white lysozyme. BCP was derived from plant biomass wastes such as dumped adzuki beans by pyrolysis without combustion under ...Biomass charcoal powder (BCP) was used as a carrier matrix for immobilization of chicken egg white lysozyme. BCP was derived from plant biomass wastes such as dumped adzuki beans by pyrolysis without combustion under nitrogen atmosphere and grinding with a jet mill. The amount of lysozyme immobilized on BCP of adzuki beans by adsorption was 11 μmol/g (0.16 g/g) at pH 7.0. The optimum pH values for free and immobilized lysozyme activities were 6.8 and 7.2, respectively. The optimum temperature for both free and immobilized lysozyme activities was 25℃. The half-life of immobilized lysozyme exhibited 1.8-fold compared to that of free lysozyme at 5℃. Moreover, the half life of immobilized lysozyme was 7 times greater than that of lysozyme at 90℃.展开更多
Biomass charcoal powder (BCP) was used as a carrier for immobilization of α-chymotrypsin through adsorption. BCP was derived from plant biomass wastes such as dumped bamboos by oxygen-free pyrolysis at low temperatur...Biomass charcoal powder (BCP) was used as a carrier for immobilization of α-chymotrypsin through adsorption. BCP was derived from plant biomass wastes such as dumped bamboos by oxygen-free pyrolysis at low temperatures and grinding with a jet mill. The activity of adsorbed α-chymotrypsin was strongly dependent upon the kind of BCP. The thermal denaturation curve of adsorbed α-chymotrypsin was shifted to high temperature, compared to that of free one. When α-chymotrypsin adsorbed onto BCP of bamboos was incubated at 45°C, the half-life of adsorbed α-chymotrypsin was 2.6 times greater than that of free one. After incubation at 45°C, the remaining activity of adsorbed α-chymotrypsin markedly depended on the kind of BCP.展开更多
No data were available on the acute oral toxicity, short-term oral toxicity of vegetable carbon in animals. This study was designed to evaluate the safety of two commercially available dietary bamboo charcoal powders(...No data were available on the acute oral toxicity, short-term oral toxicity of vegetable carbon in animals. This study was designed to evaluate the safety of two commercially available dietary bamboo charcoal powders(BCP1 and BCP2). The size distribution of the two powders was determined by a Mastersizer 2000 laser particle size analyzer prior to the in vivo safety studies. For the acute toxicity study, a single dose of 11.24 g/kg body weight of BCP1 and BCP2 was given once orally to healthy Sprague-Dawley(SD) rats. Mortality and clinical symptoms were observed and recorded for the first 30 min after treatment, at 4 h post-administration, and then at least once daily for 14 days after administration. In the repeated dose 28-day oral toxicity study, BCP1 and BCP2 were administered orally at doses of 2.81, 5.62, and 11.24 g/kg body weight for 28 days to SD rats. Animals were sacrificed and organs and blood samples were analyzed. Results showed that both BCP1 and BCP2 were micro-sized and various in size. In the acute toxicity and the repeated dose 28-day oral toxicity studies, BCP caused neither mortality nor visible signs of toxicity in rats. No significant differences were found in the relative organ weights or in biochemical parameters in BCP treated groups compared to a control group. No treatment-related histological changes were observed in the organs of these animals. Based on these data, it is concluded that the median lethal dose(LD50) of BCP for both male and female rats is more than 11. 24 g/kg body weight and the no-observed-adverse-effect level(NOAEL) is >11.24 g/kg body weight for 28 days.展开更多
Coal s volatile component, ash and fixed carbon content have different functions in different stages of a combustion process , but the traditional coal classification can precisely show its combustion property. In thi...Coal s volatile component, ash and fixed carbon content have different functions in different stages of a combustion process , but the traditional coal classification can precisely show its combustion property. In this experiment coal' s evaluation indexes ( ignition index Di), ( bum off index Df) were used to qualitatively show the ignition property and combustion ending property of coal samples. Meanwhile, considering actual heating circumstances in calciner ( in cement plants), this thesis established the relationship among the ignition index, burn off index and coal s industrial analysis value,, whifh makes it possible for the user to predict the quality of coal before using it and is very valuable in practice.展开更多
Thermal degradation processes and kinetics of composites based on ultrafinecoal powder and high density polyethylene(HDPE),linear low density polyethylene(LLDPE) or low density polyethylene(LDPE)at different compositi...Thermal degradation processes and kinetics of composites based on ultrafinecoal powder and high density polyethylene(HDPE),linear low density polyethylene(LLDPE) or low density polyethylene(LDPE)at different compositions were studied bymeans of thermogravimetric analysis(TG)and differential scanning calorimetry (DSC) inpresent work,to improve understandings in stabilization or degradation control of thecomposite.The results indicated that the coal facilitates melting of the polyethylene slightlybefore onset temperature,some chemical interactions were also observed in the compos-ite.Coal participates in chain initiation,transfer and termination of the polymer,influenceson thermal stability of composites lie in hydrogen acceptor effect of the coal.The thermaldecomposition of the coals and the polymers can be modeled via the first order parallelreactions models in low temperature range.In higher temperature case,combination ofaromatic macromolecular radical from coal with polymeric macromolecular radical givesrise to the greater activation energies of decomposition,thermal decomposition of thecomposites comply to step-by-step consecutive reactions models.Coal can be used asimportant degradation controlling additive to prepare functional materials.展开更多
As an energetic material of great interest,the work capacity of dihydroxylammonium 5,5’-bistetrazole-1,1’-diolate(TKX-50)has been questioned recently.Although some research groups have explored the reasons for the l...As an energetic material of great interest,the work capacity of dihydroxylammonium 5,5’-bistetrazole-1,1’-diolate(TKX-50)has been questioned recently.Although some research groups have explored the reasons for the low working ability of TKX-50,the plane impact experiment on powdered TKX-50 is obviously closer to the practical application,and the conclusions based on this are more guiding.Hence,we performed shock Hugoniot measurements of powdered TKX-50 between 5.65 and 16.29 GPa.The plane impact experiments of powdered TKX-50 were carried out and the shocked Raman spectra were collected.By Raman spectroscopy analysis,a new peak of powdered TKX-50 was found between19.47 GPa and 24.96 GPa,which may be caused by decomposition/phase transition and was related with the low work capacity.展开更多
The practical engineering applications of powder metallurgy (PM) Ti alloys produced through cold compaction and pressure-less sintering are impeded by poor sintering densification, embrittlement caused by excessive O ...The practical engineering applications of powder metallurgy (PM) Ti alloys produced through cold compaction and pressure-less sintering are impeded by poor sintering densification, embrittlement caused by excessive O impurities, and severe sintering deforma-tion resulting from the use of heterogeneous powder mixtures. This review presents a summary of our previous work on addressing the above challenges. Initially, we proposed a novel strategy using reaction-induced liquid phases to enhance sintering densification. Near- complete density (relative density exceeding 99%) was achieved by applying the above strategy and newly developed sintering aids. By focusing on the O-induced embrittlement issue, we determined the onset dissolution temperature of oxide films in the Ti matrix. On the basis of this finding, we established a design criterion for effective O scavengers that require reaction with oxide films before their dissol-ution. Consequently, a ductile PM Ti alloy was successfully obtained by introducing 0.3wt% NdB6 as the O scavenger. Lastly, a powder- coating strategy was adopted to address the sintering deformation issue. The ultrafine size and shell-like distribution characteristics of coating particles ensured rapid dissolution and homogeneity in the Ti matrix, thereby facilitating linear shrinkage during sintering. As a result, geometrically complex Ti alloy parts with high dimensional accuracy were fabricated by using the coated powder. Our fundament-al findings and related technical achievements enabled the development of an integrated production technology for the high-performance and accurate shaping of low-cost PM Ti alloys. Additionally, the primary engineering applications and progress in the industrialization practice of our developed technology are introduced in this review.展开更多
A hydrotalcite(layered double hydroxide, LDH) inhibitor which is suitable for the whole process of coal spontaneous combustion and a LDH inhibitor containing rare earth lanthanum elements were prepared. The inhibition...A hydrotalcite(layered double hydroxide, LDH) inhibitor which is suitable for the whole process of coal spontaneous combustion and a LDH inhibitor containing rare earth lanthanum elements were prepared. The inhibition effect and mechanism were analyzed by scanning electron microscopy(SEM),X-ray diffraction(XRD), thermal performance analysis, in-situ diffuse reflectance infrared spectroscopy and temperature-programmed experiment. The results have shown that the inhibitor containing lanthanum can play a good inhibitory role in every stage of coal oxidation. During the slow oxidation of coal samples, the inhibitor containing lanthanum ions can slow down the oxidation process of coal and increase the initial temperature of coal spontaneous combustion. At the same time, because the hydroxyl groups in LDHs are connected with-COO-groups on the coal surface through hydrogen bonds, the stability of coal is improved. With the increase of temperature, LDHs can remove interlayer water molecules and reduce the surface temperature of coal. CO release rate of coal samples decreases significantly after adding inhibitor containing lanthanum element, and the maximum inhibition rate of the inhibitor is 58.1%.展开更多
Diarrhea has become the leading cause of illness and death among infants and young children in developing countries.Clinically,patients with diarrhea showed damaged intestinal epithelial villi,usually accompanied by l...Diarrhea has become the leading cause of illness and death among infants and young children in developing countries.Clinically,patients with diarrhea showed damaged intestinal epithelial villi,usually accompanied by lactase deficiency.In this study,we evaluated the therapeutic effects of lactose-free milk powder on rats and children with diarrhea.Antibiotic-associated diarrhea(AAD)model was established by gavage with antibiotic mixture in SD rats,followed by administration of milk powder containing lactose or not.The results showed that lactose-free milk powder ameliorated A AD-related diarrhea symptoms,and accelerated the recovery from diarrhea.And 16S sequencing results indicated lactose-free milk powder contributed to increase theα-andβ-diversity of intestinal flora,and restore the intestinal microbiota disorder.In conclusion,our data demonstrate that lactose-free milk powder could alleviate diarrhea by restoring gut microbiota and intestinal barrier function.展开更多
Coal pyrolysis is a fundamental reaction in the thermal processing and utilization of coal.Investigating the behavior and kinetics of coal pyrolysis is crucial for optimizing,designing,and developing a composite riser...Coal pyrolysis is a fundamental reaction in the thermal processing and utilization of coal.Investigating the behavior and kinetics of coal pyrolysis is crucial for optimizing,designing,and developing a composite riser for the staged pyrolysis gasification process of pulverized coal.In this study,the non-isothermal pyrolysis behavior and kinetics of coal were examined at different heating rates(30,50,100,300,500,700,and 900℃/min)using thermogravimetry(TG)coupled with Fourier-transform infrared spectroscopy.Analysis of the TG/derivative TG(TG/DTG)curves indicated that coal pyrolysis mainly occurred between 300℃ and 700℃.Higher heating rates led to more volatiles being released from the coal,and a higher temperature was required to achieve rapid pyrolysis.Kinetic analysis showed that both the model-free methods(Friedman,Flynn-Wall-Ozawa,and Kissinger-Akahira-Sunose)and the model-based method(Coats-Redfern)effectively describe the coal pyrolysis process.The change in the Ea values between the two kinetic models was consistent throughout the pyrolysis process,and the most probable mechanism was the F2 model(secondary chemical reaction).In addition,the heating rate did not change the overall reaction order of the pyrolysis process;however,a higher heating rate resulted in a decrease in the Ea value during the initial pyrolysis stage.展开更多
Hydroconversion of coal tar to produce aromatic hydrocarbons(BTX)represents a crucial strategy for the highvalue hierarchical utilization of coal.This study focused on the hydrocracking of hydrorefined products derive...Hydroconversion of coal tar to produce aromatic hydrocarbons(BTX)represents a crucial strategy for the highvalue hierarchical utilization of coal.This study focused on the hydrocracking of hydrorefined products derived from coal tar to enhance the production of benzene,toluene,and xylene(BTX).Various reaction conditions,including reaction temperature,hydrogen pressure,space velocity,and hydrogen-to-oil volume ratio,were systematically explored to optimize BTX yields while also considering the process’s economic feasibility.The results indicate that increasing the reaction temperature from 360℃ to 390℃ significantly favors the production of BTX,with yields increasing from 21.42%to 41.14%.Similarly,an increase in hydrogen pressure from 4 MPa to 6 MPa boosts BTX production,with yields rising from 36.31%to 41.14%.Reducing the space velocity from 2 h^(-1) to 0.5 h^(-1) also favors the BTX production process,with yields increasing from 37.96%to 45.13%.Furthermore,raising the hydrogen-to-oil volume ratio from 750 to 1500 improves BTX yields from 41.61%to 45.44%.Through economic analysis,the optimal conditions for BTX production were identified as a reaction temperature of 390℃,hydrogen pressure of 5-6 MPa,space velocity of 1 h^(-1),and hydrogen-to-oil volume ratio of 1000,achieving a BTX yield of 43.73%.This investigation highlights the importance of a holistic evaluation of hydrocracking conditions to optimize BTX production.Furthermore,the findings offer valuable insights for the design and operation of industrial hydrocracking processes aimed at efficiently converting coal tar-derived hydrorefined feedstock into BTX.展开更多
Long-term permeability experiments have indicated that sorption-induced swelling can switch from internal to bulk depending on the evolutive sorption status.However,this sorption swelling switch mechanism has not been...Long-term permeability experiments have indicated that sorption-induced swelling can switch from internal to bulk depending on the evolutive sorption status.However,this sorption swelling switch mechanism has not been considered in current analytical permeability models.This study introduces a normalized sorption non-equilibrium index(SNEI)to characterize the sorption status,quantify the dynamical variations of matrix swelling accumulation and internal swelling partition,and formulate the sorption swelling switch model.The incorporation of this index into the extended total effective stress concept leads to an analytical transient coal permeability model.Model results show that the sorption swelling switch itself results in the permeability switch under stress-constrained conditions,while the confined bulk swelling suppresses the permeability recovery to the continuous reduction under displacement-constrained conditions.Model verifications show that current experimental observations correspond to the early stages of the transient process,and they could be extended to the whole process with these models.This study demonstrates the importance of the sorption swelling switch in determining permeability evolution using simple boundary conditions.It provides new insights into experimentally revealing the sorption swelling switch in the future,and underscores the requirement of a rigorous model for complex coupled processes in large-scale coal seams.展开更多
Discoveries of many coal seams at depths by drilling carried by Geological Survey of Pakistan in Sor Range and Harnai Gochina, extended the coal seams at depth which is challenge for mine owners to exploit feasibly. B...Discoveries of many coal seams at depths by drilling carried by Geological Survey of Pakistan in Sor Range and Harnai Gochina, extended the coal seams at depth which is challenge for mine owners to exploit feasibly. Bed to bed gypsum samplings (and their chemical analyses) of huge gypsum deposits from Sulaiman foldbelt is a base for industrialist and also planers to develop cement and gypsum industries to increase export and foreign exchange for the development of area and Pakistan. Low and high grade sedimentary iron deposits, silica sand and uranium host rocks and their extensions in Sulaiman and Kirthar foldbelts are presented. Anomalies of a few base metals arise as a result of geochemical exploration carried at part of Loralai District of Balochistan. Theropod dinosaurs were frequent in India, while Poripuchian titanosaurs (Sauropoda, Dinosauria) were frequent in Pakistan. Besides some ichnotaxa, many bone taxa such as 1 titanosauriform, 14 titanosaurian sauropod (including one new titanosaur), and 3 theropod dinosaurs are established from Pakistan. Among these 12 titanosaur species and 3 theropod species are named in about 10 km<sup>2</sup> area of Vitakri dome and 2 titanosaur species are named in about a few hundred square meter area of Mari Bohri (Kachi Bohri) which is about 10 km westward from Vitakri dome. Pakistan is a unique country which discoverd 14 diversified titanosaurs in a short area and also in a short period (67 - 66 million years ago/Ma). About 400 bones found from a few meter thick upper part of upper shale horizon of latest Maastrichtian Vitakri Formation which is base for titanosaur taxa. Cranial material is in low fraction (but include significant diverse snouts), caudal vertebrae are prominent, the cervicals, dorsals and sacrals have significant numbers, forelimb and hind limb bones have balanced fraction. Humeri, femora and tibiae are most common. To know the position of Pakistani titanosaurs among titanosaurs and sauropods, there is a need to extend list of characters for phylogenetic analyses. This broad feature list should include main characters of titanosaurs from Pakistan and also from global world.展开更多
In this paper,the durability of cement mortar prepared with a recycled-concrete fine powder(RFP)was examined;including the analysis of a variety of aspects,such as the carbonization,sulfate attack and chloride ion ero...In this paper,the durability of cement mortar prepared with a recycled-concrete fine powder(RFP)was examined;including the analysis of a variety of aspects,such as the carbonization,sulfate attack and chloride ion erosion resistance.The results indicate that the influence of RFP on these three aspects is different.The carbonization depth after 30 days and the chloride diffusion coefficient of mortar containing 10%RFP decreased by 13.3%and 28.19%.With a further increase in the RFP content,interconnected pores formed between the RFP particles,leading to an acceleration of the penetration rate of CO_(2)and Cl^(−).When the RFP content was less than 50%,the corrosion resistance coefficient of the compressive strength of the mortar was 0.84-1.05 after 90 days of sulfate attack.But the expansion and cracking of the mortar was effectively alleviated due to decrease of the gypsum production.Scanning electron microscope(SEM)analysis has confirmed that 10%RFP contributes to the formation of a dense microstructure in the cement mortar.展开更多
基金Supported by the National Key R&D Program of China(No.2018YFD0900603)the National Natural Science Foundation of China(No.31672634)+1 种基金the Open Project of Key Laboratory of Environmental Biotechnology,CAS(No.kf2018005)the Science and Technology Project of Wenzhou(No.2019ZX002-02)。
文摘Although the immunomodulatory activity of bamboo vinegar and charcoal powder(BVC)has been increasingly documented in domestic animals,the use of BVC as immunostimulant in fi sh aquaculture awaits verifi cation.In the present study,the immunostimulatory impacts of dietary BVC intake were investigated in an important aquaculture fi sh species,the African catfi sh Clarias gariepinus.Results show that the pathogen resistance of African catfi sh was signifi cantly improved by dietary BVC intake at the tested levels(0.5%-2%),as indicated by higher survival rates(approximately 1.52-1.85 times that without BVC supplementation)upon intraperitoneally injection of bacterial pathogen Aeromonas hydrophila.In addition,both the count and phagocytic activity of blood cells were signifi cantly up-regulated by a 45-day dietary supplementation of BVC.Moreover,compared to that of the control,fi sh individuals fed BVC containing diets exhibited signifi cant higher activities of superoxide dismutase(SOD),myeloperoxidase(MPO),and lysozyme(LYZ).The content of immunoglobulin M(IgM)in serum of African catfi sh was also induced by dietary BVC supplementation.Furthermore,the expression levels of interleukin-8(IL-8),toll-like receptor 1 and 5(TLR1 and TLR5),myeloid diff erentiation factor 88(MyD88),and nuclear factor kappa B(NFκB)in the head kidney were signifi cantly up-regulated.Our fi ndings indicate BVC could be an eff ective immunostimulant in teleost species,which may enhance fi sh immunity through improving hematic parameters,activating bioactive humoral molecules,and up-regulating immune related molecular pathways.
基金Supported by the National Science Foundation for Post Doctoral Scientists of China （20070411124）, Scientific and Technological Key Project of Shaanxi Province （2006k07-G19）, and Industrialization Project of Shaanxi Provincial Department of Education （06JC 11）.
文摘Thermal stability of lysozyme adsorbed on biomass charcoal powder (BCP), which was prepared from plant biomass wastes such as dumped adzuki bean, bamboo, and wood by pyrolysis without combustion under nitrogen atmosphere and comminution with a jet mill, was examined. Adsorbing lysozyme on BCP could sufficiently prevent proteins from denaturing and aggregating in an aqueous solution at high temperatures, and enhanced the refolding of thermally denatured proteins by cooling treatment. The remaining activities of lysozyme adsorbed on BCP of adzuki bean exhibited 51% by cooling treatment after the heat treatment at 90?C for 30 min, although that of native lysozyme was almost lost under the same experimental conditions. The thermostabilization effect of BCP on the remaining activity of adsorbed lysozyme was markedly dependent upon the kind of plant biomass wastes.
文摘The study on the evaporation kinetics of zinc and lead in the pellets made of Zn-Pbbearing dust mixed with carbon,in nitrogen atmosphere at the temperature range between 1 100 ℃and 1 300 ℃,shows that the reduction temperature has a significant effect on the evaporation rates of zinc and lead and that both the particle size of coal powder and the extra carbon content have no effect on the evaporation rates.The obtained activation energies for the evaporation of zinc and lead are 79.42 kJ/mol and 88.74 kJ/mol respectively.The evaporation rate of zinc is controlled by the reaction between zinc oxide and CO while that of lead is controlled by lead volatilization and the diffusion of gaseous lead through gas boundary layer covering the surface of liquid lead.
文摘Biomass charcoal powder (BCP) was used as a carrier matrix for immobilization of chicken egg white lysozyme. BCP was derived from plant biomass wastes such as dumped adzuki beans by pyrolysis without combustion under nitrogen atmosphere and grinding with a jet mill. The amount of lysozyme immobilized on BCP of adzuki beans by adsorption was 11 μmol/g (0.16 g/g) at pH 7.0. The optimum pH values for free and immobilized lysozyme activities were 6.8 and 7.2, respectively. The optimum temperature for both free and immobilized lysozyme activities was 25℃. The half-life of immobilized lysozyme exhibited 1.8-fold compared to that of free lysozyme at 5℃. Moreover, the half life of immobilized lysozyme was 7 times greater than that of lysozyme at 90℃.
文摘Biomass charcoal powder (BCP) was used as a carrier for immobilization of α-chymotrypsin through adsorption. BCP was derived from plant biomass wastes such as dumped bamboos by oxygen-free pyrolysis at low temperatures and grinding with a jet mill. The activity of adsorbed α-chymotrypsin was strongly dependent upon the kind of BCP. The thermal denaturation curve of adsorbed α-chymotrypsin was shifted to high temperature, compared to that of free one. When α-chymotrypsin adsorbed onto BCP of bamboos was incubated at 45°C, the half-life of adsorbed α-chymotrypsin was 2.6 times greater than that of free one. After incubation at 45°C, the remaining activity of adsorbed α-chymotrypsin markedly depended on the kind of BCP.
基金supported by grants from the National Natural Science Foundation of China(No.81030053)the Doctoral Foundation of the Chinese Ministry of Education(No.20120181110040)
文摘No data were available on the acute oral toxicity, short-term oral toxicity of vegetable carbon in animals. This study was designed to evaluate the safety of two commercially available dietary bamboo charcoal powders(BCP1 and BCP2). The size distribution of the two powders was determined by a Mastersizer 2000 laser particle size analyzer prior to the in vivo safety studies. For the acute toxicity study, a single dose of 11.24 g/kg body weight of BCP1 and BCP2 was given once orally to healthy Sprague-Dawley(SD) rats. Mortality and clinical symptoms were observed and recorded for the first 30 min after treatment, at 4 h post-administration, and then at least once daily for 14 days after administration. In the repeated dose 28-day oral toxicity study, BCP1 and BCP2 were administered orally at doses of 2.81, 5.62, and 11.24 g/kg body weight for 28 days to SD rats. Animals were sacrificed and organs and blood samples were analyzed. Results showed that both BCP1 and BCP2 were micro-sized and various in size. In the acute toxicity and the repeated dose 28-day oral toxicity studies, BCP caused neither mortality nor visible signs of toxicity in rats. No significant differences were found in the relative organ weights or in biochemical parameters in BCP treated groups compared to a control group. No treatment-related histological changes were observed in the organs of these animals. Based on these data, it is concluded that the median lethal dose(LD50) of BCP for both male and female rats is more than 11. 24 g/kg body weight and the no-observed-adverse-effect level(NOAEL) is >11.24 g/kg body weight for 28 days.
基金Funded by Foundation for University Key Teacher by the Ministry of Mutation.
文摘Coal s volatile component, ash and fixed carbon content have different functions in different stages of a combustion process , but the traditional coal classification can precisely show its combustion property. In this experiment coal' s evaluation indexes ( ignition index Di), ( bum off index Df) were used to qualitatively show the ignition property and combustion ending property of coal samples. Meanwhile, considering actual heating circumstances in calciner ( in cement plants), this thesis established the relationship among the ignition index, burn off index and coal s industrial analysis value,, whifh makes it possible for the user to predict the quality of coal before using it and is very valuable in practice.
基金National Natural Science Foundation of China(20276056)the Science and Technology Key Problem Plan of Shannxi Province(No.2000K10-G9)
文摘Thermal degradation processes and kinetics of composites based on ultrafinecoal powder and high density polyethylene(HDPE),linear low density polyethylene(LLDPE) or low density polyethylene(LDPE)at different compositions were studied bymeans of thermogravimetric analysis(TG)and differential scanning calorimetry (DSC) inpresent work,to improve understandings in stabilization or degradation control of thecomposite.The results indicated that the coal facilitates melting of the polyethylene slightlybefore onset temperature,some chemical interactions were also observed in the compos-ite.Coal participates in chain initiation,transfer and termination of the polymer,influenceson thermal stability of composites lie in hydrogen acceptor effect of the coal.The thermaldecomposition of the coals and the polymers can be modeled via the first order parallelreactions models in low temperature range.In higher temperature case,combination ofaromatic macromolecular radical from coal with polymeric macromolecular radical givesrise to the greater activation energies of decomposition,thermal decomposition of thecomposites comply to step-by-step consecutive reactions models.Coal can be used asimportant degradation controlling additive to prepare functional materials.
基金supported by the National Natural Science Foundation of China(Grant No.12072299)the Fundamental Research Funds for the Central Universities(Grant No.2682020ZT102)。
文摘As an energetic material of great interest,the work capacity of dihydroxylammonium 5,5’-bistetrazole-1,1’-diolate(TKX-50)has been questioned recently.Although some research groups have explored the reasons for the low working ability of TKX-50,the plane impact experiment on powdered TKX-50 is obviously closer to the practical application,and the conclusions based on this are more guiding.Hence,we performed shock Hugoniot measurements of powdered TKX-50 between 5.65 and 16.29 GPa.The plane impact experiments of powdered TKX-50 were carried out and the shocked Raman spectra were collected.By Raman spectroscopy analysis,a new peak of powdered TKX-50 was found between19.47 GPa and 24.96 GPa,which may be caused by decomposition/phase transition and was related with the low work capacity.
基金supported by the National Natural Science Foundation of China (Nos.52074254 and 52174349)the CAS Project for Young Scientists in Basic Research,China (No.YSBR-025)+3 种基金the Shandong Provincial Science and Technology Innovation Project,China (No.2019JZZY010363)the Key Projects of International Cooperation,China (No.122111KYSB20200034)the Project of Key Laboratory of Science and Technology on Particle Materials,China (No.CXJJ-22S043)Chinese Academy of Sciences.This work was also financially supported by the Selection of Best Candidates to Undertake Key Research Projects,China (No.211110230200).
文摘The practical engineering applications of powder metallurgy (PM) Ti alloys produced through cold compaction and pressure-less sintering are impeded by poor sintering densification, embrittlement caused by excessive O impurities, and severe sintering deforma-tion resulting from the use of heterogeneous powder mixtures. This review presents a summary of our previous work on addressing the above challenges. Initially, we proposed a novel strategy using reaction-induced liquid phases to enhance sintering densification. Near- complete density (relative density exceeding 99%) was achieved by applying the above strategy and newly developed sintering aids. By focusing on the O-induced embrittlement issue, we determined the onset dissolution temperature of oxide films in the Ti matrix. On the basis of this finding, we established a design criterion for effective O scavengers that require reaction with oxide films before their dissol-ution. Consequently, a ductile PM Ti alloy was successfully obtained by introducing 0.3wt% NdB6 as the O scavenger. Lastly, a powder- coating strategy was adopted to address the sintering deformation issue. The ultrafine size and shell-like distribution characteristics of coating particles ensured rapid dissolution and homogeneity in the Ti matrix, thereby facilitating linear shrinkage during sintering. As a result, geometrically complex Ti alloy parts with high dimensional accuracy were fabricated by using the coated powder. Our fundament-al findings and related technical achievements enabled the development of an integrated production technology for the high-performance and accurate shaping of low-cost PM Ti alloys. Additionally, the primary engineering applications and progress in the industrialization practice of our developed technology are introduced in this review.
基金Funded by National Natural Science Foundation of China (No.52074218)。
文摘A hydrotalcite(layered double hydroxide, LDH) inhibitor which is suitable for the whole process of coal spontaneous combustion and a LDH inhibitor containing rare earth lanthanum elements were prepared. The inhibition effect and mechanism were analyzed by scanning electron microscopy(SEM),X-ray diffraction(XRD), thermal performance analysis, in-situ diffuse reflectance infrared spectroscopy and temperature-programmed experiment. The results have shown that the inhibitor containing lanthanum can play a good inhibitory role in every stage of coal oxidation. During the slow oxidation of coal samples, the inhibitor containing lanthanum ions can slow down the oxidation process of coal and increase the initial temperature of coal spontaneous combustion. At the same time, because the hydroxyl groups in LDHs are connected with-COO-groups on the coal surface through hydrogen bonds, the stability of coal is improved. With the increase of temperature, LDHs can remove interlayer water molecules and reduce the surface temperature of coal. CO release rate of coal samples decreases significantly after adding inhibitor containing lanthanum element, and the maximum inhibition rate of the inhibitor is 58.1%.
基金supported by the project of two children’s dairy products (201704810610483)。
文摘Diarrhea has become the leading cause of illness and death among infants and young children in developing countries.Clinically,patients with diarrhea showed damaged intestinal epithelial villi,usually accompanied by lactase deficiency.In this study,we evaluated the therapeutic effects of lactose-free milk powder on rats and children with diarrhea.Antibiotic-associated diarrhea(AAD)model was established by gavage with antibiotic mixture in SD rats,followed by administration of milk powder containing lactose or not.The results showed that lactose-free milk powder ameliorated A AD-related diarrhea symptoms,and accelerated the recovery from diarrhea.And 16S sequencing results indicated lactose-free milk powder contributed to increase theα-andβ-diversity of intestinal flora,and restore the intestinal microbiota disorder.In conclusion,our data demonstrate that lactose-free milk powder could alleviate diarrhea by restoring gut microbiota and intestinal barrier function.
基金the financial support from the National Natural Science Foundation of China(Grant No.21576293 and 21576294)。
文摘Coal pyrolysis is a fundamental reaction in the thermal processing and utilization of coal.Investigating the behavior and kinetics of coal pyrolysis is crucial for optimizing,designing,and developing a composite riser for the staged pyrolysis gasification process of pulverized coal.In this study,the non-isothermal pyrolysis behavior and kinetics of coal were examined at different heating rates(30,50,100,300,500,700,and 900℃/min)using thermogravimetry(TG)coupled with Fourier-transform infrared spectroscopy.Analysis of the TG/derivative TG(TG/DTG)curves indicated that coal pyrolysis mainly occurred between 300℃ and 700℃.Higher heating rates led to more volatiles being released from the coal,and a higher temperature was required to achieve rapid pyrolysis.Kinetic analysis showed that both the model-free methods(Friedman,Flynn-Wall-Ozawa,and Kissinger-Akahira-Sunose)and the model-based method(Coats-Redfern)effectively describe the coal pyrolysis process.The change in the Ea values between the two kinetic models was consistent throughout the pyrolysis process,and the most probable mechanism was the F2 model(secondary chemical reaction).In addition,the heating rate did not change the overall reaction order of the pyrolysis process;however,a higher heating rate resulted in a decrease in the Ea value during the initial pyrolysis stage.
文摘Hydroconversion of coal tar to produce aromatic hydrocarbons(BTX)represents a crucial strategy for the highvalue hierarchical utilization of coal.This study focused on the hydrocracking of hydrorefined products derived from coal tar to enhance the production of benzene,toluene,and xylene(BTX).Various reaction conditions,including reaction temperature,hydrogen pressure,space velocity,and hydrogen-to-oil volume ratio,were systematically explored to optimize BTX yields while also considering the process’s economic feasibility.The results indicate that increasing the reaction temperature from 360℃ to 390℃ significantly favors the production of BTX,with yields increasing from 21.42%to 41.14%.Similarly,an increase in hydrogen pressure from 4 MPa to 6 MPa boosts BTX production,with yields rising from 36.31%to 41.14%.Reducing the space velocity from 2 h^(-1) to 0.5 h^(-1) also favors the BTX production process,with yields increasing from 37.96%to 45.13%.Furthermore,raising the hydrogen-to-oil volume ratio from 750 to 1500 improves BTX yields from 41.61%to 45.44%.Through economic analysis,the optimal conditions for BTX production were identified as a reaction temperature of 390℃,hydrogen pressure of 5-6 MPa,space velocity of 1 h^(-1),and hydrogen-to-oil volume ratio of 1000,achieving a BTX yield of 43.73%.This investigation highlights the importance of a holistic evaluation of hydrocracking conditions to optimize BTX production.Furthermore,the findings offer valuable insights for the design and operation of industrial hydrocracking processes aimed at efficiently converting coal tar-derived hydrorefined feedstock into BTX.
基金supported by the Australian Research Council(Grant No.DP200101293)the National Natural Science Foundation of China(Grant No.42202286)the Zhejiang Collaborative Innovation Center for Prevention and Control of Mountain Geological Hazards(Grant No.PCMGH-2017-Z-02).
文摘Long-term permeability experiments have indicated that sorption-induced swelling can switch from internal to bulk depending on the evolutive sorption status.However,this sorption swelling switch mechanism has not been considered in current analytical permeability models.This study introduces a normalized sorption non-equilibrium index(SNEI)to characterize the sorption status,quantify the dynamical variations of matrix swelling accumulation and internal swelling partition,and formulate the sorption swelling switch model.The incorporation of this index into the extended total effective stress concept leads to an analytical transient coal permeability model.Model results show that the sorption swelling switch itself results in the permeability switch under stress-constrained conditions,while the confined bulk swelling suppresses the permeability recovery to the continuous reduction under displacement-constrained conditions.Model verifications show that current experimental observations correspond to the early stages of the transient process,and they could be extended to the whole process with these models.This study demonstrates the importance of the sorption swelling switch in determining permeability evolution using simple boundary conditions.It provides new insights into experimentally revealing the sorption swelling switch in the future,and underscores the requirement of a rigorous model for complex coupled processes in large-scale coal seams.
文摘Discoveries of many coal seams at depths by drilling carried by Geological Survey of Pakistan in Sor Range and Harnai Gochina, extended the coal seams at depth which is challenge for mine owners to exploit feasibly. Bed to bed gypsum samplings (and their chemical analyses) of huge gypsum deposits from Sulaiman foldbelt is a base for industrialist and also planers to develop cement and gypsum industries to increase export and foreign exchange for the development of area and Pakistan. Low and high grade sedimentary iron deposits, silica sand and uranium host rocks and their extensions in Sulaiman and Kirthar foldbelts are presented. Anomalies of a few base metals arise as a result of geochemical exploration carried at part of Loralai District of Balochistan. Theropod dinosaurs were frequent in India, while Poripuchian titanosaurs (Sauropoda, Dinosauria) were frequent in Pakistan. Besides some ichnotaxa, many bone taxa such as 1 titanosauriform, 14 titanosaurian sauropod (including one new titanosaur), and 3 theropod dinosaurs are established from Pakistan. Among these 12 titanosaur species and 3 theropod species are named in about 10 km<sup>2</sup> area of Vitakri dome and 2 titanosaur species are named in about a few hundred square meter area of Mari Bohri (Kachi Bohri) which is about 10 km westward from Vitakri dome. Pakistan is a unique country which discoverd 14 diversified titanosaurs in a short area and also in a short period (67 - 66 million years ago/Ma). About 400 bones found from a few meter thick upper part of upper shale horizon of latest Maastrichtian Vitakri Formation which is base for titanosaur taxa. Cranial material is in low fraction (but include significant diverse snouts), caudal vertebrae are prominent, the cervicals, dorsals and sacrals have significant numbers, forelimb and hind limb bones have balanced fraction. Humeri, femora and tibiae are most common. To know the position of Pakistani titanosaurs among titanosaurs and sauropods, there is a need to extend list of characters for phylogenetic analyses. This broad feature list should include main characters of titanosaurs from Pakistan and also from global world.
基金This work is supported by the Zhuhai Science and Technology Project(ZH22036203200015PWC)the Open Foundation of State Key Laboratory of Subtropical Building Science(2022ZB20).
文摘In this paper,the durability of cement mortar prepared with a recycled-concrete fine powder(RFP)was examined;including the analysis of a variety of aspects,such as the carbonization,sulfate attack and chloride ion erosion resistance.The results indicate that the influence of RFP on these three aspects is different.The carbonization depth after 30 days and the chloride diffusion coefficient of mortar containing 10%RFP decreased by 13.3%and 28.19%.With a further increase in the RFP content,interconnected pores formed between the RFP particles,leading to an acceleration of the penetration rate of CO_(2)and Cl^(−).When the RFP content was less than 50%,the corrosion resistance coefficient of the compressive strength of the mortar was 0.84-1.05 after 90 days of sulfate attack.But the expansion and cracking of the mortar was effectively alleviated due to decrease of the gypsum production.Scanning electron microscope(SEM)analysis has confirmed that 10%RFP contributes to the formation of a dense microstructure in the cement mortar.
