A new category of lithium greases was synthesized by using poly-a-olefin(PAO8) and alkyl-tetralin as base oil, where the alkyl-tetralins were synthesized by the alkylation of tetralin and olefins. The influence of thi...A new category of lithium greases was synthesized by using poly-a-olefin(PAO8) and alkyl-tetralin as base oil, where the alkyl-tetralins were synthesized by the alkylation of tetralin and olefins. The influence of thickener concentration, alkyl-tetralin content and type of blend oils on the rheological and tribological performance of lithium grease was investigated. The microstructures of soap fibers were measured to reveal the structure-property correlations. The concentration of thickener and alkyl-tetralin content obviously affect the lubricating performance of lithium grease, while the molecular structure of alkyltetralin has no obvious impact on their properties. It was found that alkyl-tetralin could significantly enhance the thickening ability of PAO8 base oils, and decrease the amount of thickeners by 1.5%(mass).Lithium greases prepared using 20%(mass) alkyl-tetralin as co-base oil exhibited high colloidal stability,excellent rheological behaviors and tribological properties.展开更多
Naphthenic base oil is an important lubricating base oil and very scarce in the global petroleum resources.Herein,a series of alkylated tetralin fluids similar to naphthenic base oils were produced by the alkylation o...Naphthenic base oil is an important lubricating base oil and very scarce in the global petroleum resources.Herein,a series of alkylated tetralin fluids similar to naphthenic base oils were produced by the alkylation of tetralin and a-olefins(n-hexene,n-octene,n-decene)with ionic liquid Et_3NHCl/AlCl_(3)as the catalyst,where the applied raw materials are totally derived from the coal chemical industry.The product composition could be controlled by adjusting the feeding ratio of tetralin and olefin.The synthetic fluids were evaluated as lubricating base oils to reveal the structure-property correlations.Their principal physicochemical and tribological properties depend on the chain-length of a-olefins and the number of alkyl groups onto the aromatic rings.Bis-(octyl-or decyl-)alkyl tetralin exhibited good properties in terms of viscosity,thermo-oxidation stability and pour point,as well as friction-reducing and anti-wear performance,showing great potential for producing naphthenic base synthetic oils from coal-based chemicals.展开更多
This paper briefly reviews ionospheric irregularities that occur in the E and F regions at mid-latitudes. Sporadic E(ES) is a common ionospheric irregularity phenomenon that is first noticed in the E layer. ES mainly ...This paper briefly reviews ionospheric irregularities that occur in the E and F regions at mid-latitudes. Sporadic E(ES) is a common ionospheric irregularity phenomenon that is first noticed in the E layer. ES mainly appears during daytime in summer hemispheres, and is formed primarily from neutral wind shear in the mesosphere and lower thermosphere(MLT) region. Field-aligned irregularity(FAI) in the E region is also observed by Very High Frequency(VHF) radar in mid-latitude regions. FAI frequently occurs after sunset in summer hemispheres, and spectrum features of E region FAI echoes suggest that type-2 irregularity is dominant in the nighttime ionosphere. A close relationship between ES and E region FAI implies that ES may be a possible source of E region FAI in the nighttime ionosphere. Strong neutral wind shear, steep ES plasma density gradient, and a polarized electric field are the significant factors affecting the formation of E region FAI. At mid-latitudes, joint observational experiments including ionosonde, VHF radar, Global Positioning System(GPS) stations, and all-sky optical images have revealed strong connections across different scales of ionospheric irregularities in the nighttime F region, such as spread F(SF), medium-scale traveling ionospheric disturbances(MSTID), and F region FAI.Observations suggest that different scales of ionospheric irregularities are generally attributed to the Perkins instability and subsequently excited gradient drift instability. Nighttime MSTID can further evolve into small-scale structures through a nonlinear cascade process when a steep plasma density gradient exists at the bottom of the F region. In addition, the effect of ionospheric electrodynamic coupling processes, including ionospheric E-F coupling and inter-hemispheric coupling on the generation of ionospheric irregularities, becomes more prominent due to the significant dip angle and equipotentiality of magnetic field lines in the mid-latitude ionosphere. Polarized electric fields can map to different ionospheric regions and excite plasma instabilities which form ionospheric irregularities. Nevertheless,the mapping efficiency of a polarized electric field depends on the ionospheric background and spatial scale of the field.展开更多
With the development of coal chemical industry,large amounts of naphthalene and n-butene are produced,and converting them into high value-added products through alkylation has gained particular importance and interest...With the development of coal chemical industry,large amounts of naphthalene and n-butene are produced,and converting them into high value-added products through alkylation has gained particular importance and interest.In this work,liquid coordination complexes(LCCs)were used as acid catalysts for the first time in the naphthalene alkylation reaction under mild conditions to obtain multibutylnaphthalenes with high yield.Various reaction conditions were thoroughly investigated.The LCC consisting of urea and AlCl_(3) showed excellent catalytic performance under optimal reaction conditions,giving 100%conversion of naphthalene and 99.66%selectivity towards multi-butylnaphthalenes.Combining the catalyst properties and catalytic results,a plausible reaction mechanism was proposed.The lubricating properties of the synthesized products were investigated for their potential application as lubricating base oils.The synthesized multi-butylnaphthalenes showed comparable physicochemical properties and tribological performances as the commercial cycloalkyl base oil.展开更多
With the increasing severity of environmental problems,many countries have set energy transition targets to promote the realization of the Paris Agreement.There has been a global consensus on utilizing solar energy re...With the increasing severity of environmental problems,many countries have set energy transition targets to promote the realization of the Paris Agreement.There has been a global consensus on utilizing solar energy resources as alternatives to conventional sources to support this energy transition.In this regard,analyzing the“location,”“quantity,”and“quality”of global solar energy resources will not only assist an individual country to efficiently utilize these resources but also promote the realization of large-scale intercontinental resource utilization and complementation.This study established the basic database,model methods,and platform tools for global solar energy assessment,Then,a global solar energy resource assessment was conducted,which included the theoretical reserves(TRs),technical installed potential capacity(TPIC),and average development cost(ADC).A comparative analysis of the assessment results for all continents was also performed.After that,based on big data analysis and geographic information system(GIS)calculations,the distribution characteristics of the global solar power TPIC were calculated with the two core indicators,namely the capacity factor and ADC.Furthermore,a data-driven quantitative evaluation of the refined development potential of solar energy resources was performed.Finally,the reasonableness and coincidence analysis of the resource assessment results were verified using data from global and specifically Chinese photovoltaic(PV)bases.展开更多
Background: More and more chronic kidney disease (CKD) patients are accompanied with hyperuricaemia. As is known, hyperuricaemia is an independent hazard of both cardiovascular diseases (CVD) and chronic kidney diseas...Background: More and more chronic kidney disease (CKD) patients are accompanied with hyperuricaemia. As is known, hyperuricaemia is an independent hazard of both cardiovascular diseases (CVD) and chronic kidney diseases. We aim at identifying Single Nucleotide Polymorphism (SNP) difference of hURAT1 (rs7932775) and ABCG2 (rs3825016) on CKD patient with hyperuricemia and/or gout. Methods: All forty-two CKD patients were divided into two groups: hyperuricemia, and control group. 24 hours urine sample and serum were prepared for testing biochemistry parameters. The polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method is used to analyze hURAT1 and ABCG2 single nucleotide polymorphisms in different groups. Results: 17 patients have CT SNP of hURAT1 (rs7932775) and 13 patients have CT SNP of ABCG2 (rs3825016) in hyperuricemia group, while only 5 persons and 6 persons have the same mutations in control group respectively. 7 patients have CT SNP of both hURAT1 (rs7932775) and ABCG2 (rs3825016) in hyperuricemia group, while only 2 persons have the same mutations in control group. CT mutation rates of hURAT1 (rs7932775) and ABCG2 (rs3825016) in hyperuricemia group were 60.7% (17/28) and 50% (13/28) respectively, higher than that of control group (35.7% (5/14) and 42.8% (6/14)). What is more, Double SNP mutations in both hURAT1 (rs7932775) and ABCG2 (rs3825016) in hyperuricemia group were 25% (7/28), higher than that of control group (14.2%, 2/14). Conclusion: There are higher mutation rates of CT SNP in hURAT1 (rs7932775) and/or ABCG2 (rs3825016) in hyperuricemia group. We can conclude that hyperuricemia is a high risk factor in progress of CKD, which is necessary to take measures of decreasing serum uric acid to delay CKD progress.展开更多
Through investigating both users' and librarians' perceptions of the relative importance of the major criteria governing the selection of digital resources, we attempted to develop a criterion weight framework...Through investigating both users' and librarians' perceptions of the relative importance of the major criteria governing the selection of digital resources, we attempted to develop a criterion weight framework for a library's selection of digital resources, which can meet both the users' requirements and the library's goal of developing digital collections. The respective weight of each specific criterion is decided through the Analytic Hierarchy Process(AHP) Method. The findings of this study indicate that, when assigning weights to the selection criteria, it is important to consult the opinions of a wide crosssection of people, especially the views of different users. As a result, the digital resource selection system characterized by the criteria weights can reflect more comprehensively the users' requirements, and meanwhile it enables librarians' more rational selection of digital resources.展开更多
Conversational large language models(LLMs)such as ChatGPT and GPT-4 have recently exhibited remarkable capabilities across various domains,capturing widespread attention from the public.To facilitate this line of rese...Conversational large language models(LLMs)such as ChatGPT and GPT-4 have recently exhibited remarkable capabilities across various domains,capturing widespread attention from the public.To facilitate this line of research,in this paper,we report the development of MOSS,an open-sourced conversational LLM that contains 16 B parameters and can perform a variety of instructions in multi-turn interactions with humans.The base model of MOSS is pre-trained on large-scale unlabeled English,Chinese,and code data.To optimize the model for dialogue,we generate 1.1 M synthetic conversations based on user prompts collected through our earlier versions of the model API.We then perform preference-aware training on preference data annotated from AI feedback.Evaluation results on real-world use cases and academic benchmarks demonstrate the effectiveness of the proposed approaches.In addition,we present an effective practice to augment MOSS with several external tools.Through the development of MOSS,we have established a complete technical roadmap for large language models from pre-training,supervised fine-tuning to alignment,verifying the feasibility of chatGPT under resource-limited conditions and providing a reference for both the academic and industrial communities.Model weights and code are publicly available at https://github.com/OpenMOSS/MOSS.展开更多
Mineralization of benzene,toluene,and xylene (BTX) with high efficiency at room temperature is still a challenge for the purification of indoor air.In this work,a foam Ti/Sb-Sn O2/β-Pb O_(2)anode catalyst was prepare...Mineralization of benzene,toluene,and xylene (BTX) with high efficiency at room temperature is still a challenge for the purification of indoor air.In this work,a foam Ti/Sb-Sn O2/β-Pb O_(2)anode catalyst was prepared for electrocatalytically oxidizing gaseous toluene in an all-solid cell at ambient temperature.The complex Ti/Sb-Sn O_(2)/β-Pb O_(2)anode,which was prepared by sequentially deposing Sb-Sn O_(2)and β-Pb O_(2)on a foam Ti substrate,shows high electrocatalytic oxidation efficiency of toluene (80%) at 7 hr of reaction and high CO_(2)selectivity (94.9%) under an optimized condition,i.e.,a cell voltage of 2.0 V,relative humidity of60%and a flow rate of 100 m L/min.The better catalytic performance can be ascribed to the high production rate of·OH radicals from discharging adsorbed water and the inhibition of oxygen evolution on the surface of foam Ti/Sb-Sn O_(2)/β-Pb O_(2)anode when compared with the foam Ti/Sb-Sn O_(2)anode.Our results demonstrate that prepared complex electrodes can be potentially used for electrocatalytic removal of gaseous toluene at room temperature with a good performance.展开更多
The chemoselective hydrogenation ofα,β-unsaturated aldehydes is a key strategy for the synthesis of fine chemicals.Herein,we developed an efficient method of depositing Pt particles on FeO_(x)/SBA-15.This strategy i...The chemoselective hydrogenation ofα,β-unsaturated aldehydes is a key strategy for the synthesis of fine chemicals.Herein,we developed an efficient method of depositing Pt particles on FeO_(x)/SBA-15.This strategy is dependent on using a platinumdivinyltetramethyldisiloxane complex(Pt^(0)-DVTMS)as the precursor,which we demonstrate can be removed through a H_(2)-treatment under mild conditions.This,in turn,allowed for the synthesis of catalysts with well dispersed Pt particles.The presence of FeO_(x) species also aided Pt dispersion;when coated onto SBA-15,FeO_(x) strongly interacted with dissociated Pt species,inhibiting both Pt aggregation and metal leaching.Using cinnamaldehyde as a modelα,β-unsaturated aldehyde,it was demonstrated that this catalyst was highly selective towards the unsaturated alcohol and no obvious loss in activity was observed over five recycles.This catalyst was determined to be significantly more effective than an analogous catalyst prepared using chloroplatinic acid as a precursor,evidencing the importance of using the Pt0-DVTMS precursor.We corroborate the excellent catalytic performance to highly dispersed Pt-species,whereby Pt0 and Pt^(2+) play a critical role in activating H_(2) and the C=O bond.This research demonstrates that the Pt precursor can have a significant impact on the physicochemical properties and thus,the performance of the final catalyst.It also evidences how metal support interactions can dramatically influence selectivity in such hydrogenation reactions.This novel catalyst preparation protocol,using a DVTMS ligand for Pt impregnation,offers a facile approach to the design of multi-component heterogeneous catalysts.展开更多
This paper is concerned with the finite element method for nonlinear Hamiltonian systems from three aspects: conservation of energy, symplicity, and the global error. To study the symplecticity of the finite element ...This paper is concerned with the finite element method for nonlinear Hamiltonian systems from three aspects: conservation of energy, symplicity, and the global error. To study the symplecticity of the finite element methods, we use an analytical method rather than the commonly used algebraic method. We prove optimal order of convergence at the nodes tn for mid-long time and demonstrate the symplecticity of high accuracy. The proofs depend strongly on superconvergence analysis. Numerical experiments show that the proposed method can preserve the energy very well and also can make the global trajectory error small for long time.展开更多
The aim of this study was to uncover ways to mitigate greenhouse gas(GHG) emissions and reduce energy consumption during the composting process. We assessed the effects of different aeration rates(0, 0.18, 0.36, an...The aim of this study was to uncover ways to mitigate greenhouse gas(GHG) emissions and reduce energy consumption during the composting process. We assessed the effects of different aeration rates(0, 0.18, 0.36, and 0.54 L/(kg dry matter(dm)·min)) and methods(continuous and intermittent) on GHG emissions. Pig feces and corn stalks were mixed at a ratio of 7:1. The composting process lasted for 10 weeks, and the compost was turned approximately every 2 weeks. Results showed that both aeration rate and method significantly affected GHG emissions. Higher aeration rates increased NH3 and N2O losses,but reduced CH4 emissions. The exception is that the CH4 emission of the passive aeration treatment was lower than that of the low aeration rate treatment. Without forced aeration,the CH4 diffusion rates in the center of the piles were very low and part of the CH4 was oxidized in the surface layer. Intermittent aeration reduced NH3 and CH4 losses, but significantly increased N2 O production during the maturing periods. Intermittent aeration increased the nitrification/denitrification alternation and thus enhanced the N2 O production. Forced aeration treatments had higher GHG emission rates than the passive aeration treatment. Forced aeration accelerated the maturing process, but could not improve the quality of the end product. Compared with continuous aeration, intermittent aeration could increase the O2 supply efficiency and reduced the total GHG emission by 17.8%, and this reduction increased to 47.4% when composting was ended after 36 days.展开更多
Tetrastigma hemsleyanum(T.hemsleyanum)has been regarded as an anticancer food in China.However,its corresponding mechanisms remains unclear.Thus,in this study,the antitumor activity of flavones-rich fraction of root o...Tetrastigma hemsleyanum(T.hemsleyanum)has been regarded as an anticancer food in China.However,its corresponding mechanisms remains unclear.Thus,in this study,the antitumor activity of flavones-rich fraction of root of T.hemsleyanum(FRTH)was investigated in vitro and in vivo.The results indicated that FRTH could inhibit the proliferation and migration of human hepatoellular carcinomas(HepG2)cells in vitro by the phosphatidylinositol 3-kinase/protein kinase B(PI3K/AKT)pathway.FRTH could increase the level of reactive oxygen species and change the mitochondrial membrane potential in HepG2 cells.In addition,FRTH treatment(300 mg/kg and 600 mg/kg,body weight)significantly suppressed tumor growth on HepG2 tumor-bearing nude mice.Besides,immunohistochemistry assays and western blotting revealed that FRTH enhanced the expression level of Bcl-2 associated X protein/B-cell lymphoma-2(Bax/Bcl-2),cytochrome C,caspase-3,caspase-9,and cleaved-caspase-3,and downregulated the expression level of platelet endothelial cell adhesion molecule-1(CD31),ki67,and vascular endothelial growth factor(VEGF)factor in HepG2 tumor-bearing mice.Our study suggests T.hemsleyanum as a kind of promising candidate medicine for liver cancer treatment.展开更多
Metal oxide/hydroxide-based nanocomposite adsorbents with porous supporting matrices have been recognized as efficient adsorbents for phosphorus recovery.Aiming at satisfying increasingly restrictive environmental req...Metal oxide/hydroxide-based nanocomposite adsorbents with porous supporting matrices have been recognized as efficient adsorbents for phosphorus recovery.Aiming at satisfying increasingly restrictive environmental requirements involving improving metal site utilization and lowering metal leakage risk,a glycol-solvothermal confined-space synthesis strategy was proposed for the fabrication of Fe OOH/anion exchanger nanocomposites(Fe/900s)with enhanced metal site utilization and reduced metal leakage risk.Compared to composites prepared using alkaline precipitation methods,Fe/900s performed comparably,with a high adsorption capacity of 19.05 mg-P/g with an initial concentration of 10 mg-P/L,a high adsorption selectivity of 8.2 mg-P/g in the presence of 500 mg-SO_(4)^(2-)/L,and high long-term resilience(with a capacity loss of~14%after five cycles),along with substantially lower Fe loading amount(4.11 wt.%)and Fe leakage percentage.Mechanistic investigation demonstrated that contribution of the specific Fe OOH sites to phosphate adsorption increased substantially(up to 50.97%under the optimal conditions),in which Fe(Ⅲ)-OH was the dominant efficient species.The side effects of an excessively long reaction time,which included quaternary ammonium decomposition,Fe OOH aggregation,and Fe(Ⅲ)reduction,were discussed as guidance for optimizing the synthesis strategy.The glycol-solvothermal strategy provides a facile solution to environmental problems through nanocrystal growth engineering in a confined space.展开更多
基金financially supported by the National Natural Science Foundation of China (U1910202, 21978194)the Key Research and Development Program of Shanxi Province (202102090301005)+1 种基金the Fund for Shanxi “1331 Project”the Shanxi Natural Science Foundation for Young Scientists (202103021223064)。
文摘A new category of lithium greases was synthesized by using poly-a-olefin(PAO8) and alkyl-tetralin as base oil, where the alkyl-tetralins were synthesized by the alkylation of tetralin and olefins. The influence of thickener concentration, alkyl-tetralin content and type of blend oils on the rheological and tribological performance of lithium grease was investigated. The microstructures of soap fibers were measured to reveal the structure-property correlations. The concentration of thickener and alkyl-tetralin content obviously affect the lubricating performance of lithium grease, while the molecular structure of alkyltetralin has no obvious impact on their properties. It was found that alkyl-tetralin could significantly enhance the thickening ability of PAO8 base oils, and decrease the amount of thickeners by 1.5%(mass).Lithium greases prepared using 20%(mass) alkyl-tetralin as co-base oil exhibited high colloidal stability,excellent rheological behaviors and tribological properties.
基金financially supported by the National Natural Science Foundation of China(U1910202,21978194,22078219 and 22072173)the Fund for Shanxi“1331 Project”the Key Research and Development Program of Shanxi Province(202102090301005)。
文摘Naphthenic base oil is an important lubricating base oil and very scarce in the global petroleum resources.Herein,a series of alkylated tetralin fluids similar to naphthenic base oils were produced by the alkylation of tetralin and a-olefins(n-hexene,n-octene,n-decene)with ionic liquid Et_3NHCl/AlCl_(3)as the catalyst,where the applied raw materials are totally derived from the coal chemical industry.The product composition could be controlled by adjusting the feeding ratio of tetralin and olefin.The synthetic fluids were evaluated as lubricating base oils to reveal the structure-property correlations.Their principal physicochemical and tribological properties depend on the chain-length of a-olefins and the number of alkyl groups onto the aromatic rings.Bis-(octyl-or decyl-)alkyl tetralin exhibited good properties in terms of viscosity,thermo-oxidation stability and pour point,as well as friction-reducing and anti-wear performance,showing great potential for producing naphthenic base synthetic oils from coal-based chemicals.
基金supported by the National Natural Science Foundation of China (No. 41574146, 41774162, 42074187)the National Key R&D Program of China (No. 2018YFC1503506)+1 种基金the Excellent Youth Foundation of Hubei Provincial Natural Science Foundation (No. 2019CFA054)the Foundation of the National Key Laboratory of Electromagnetic Environment (No. 20200101)。
文摘This paper briefly reviews ionospheric irregularities that occur in the E and F regions at mid-latitudes. Sporadic E(ES) is a common ionospheric irregularity phenomenon that is first noticed in the E layer. ES mainly appears during daytime in summer hemispheres, and is formed primarily from neutral wind shear in the mesosphere and lower thermosphere(MLT) region. Field-aligned irregularity(FAI) in the E region is also observed by Very High Frequency(VHF) radar in mid-latitude regions. FAI frequently occurs after sunset in summer hemispheres, and spectrum features of E region FAI echoes suggest that type-2 irregularity is dominant in the nighttime ionosphere. A close relationship between ES and E region FAI implies that ES may be a possible source of E region FAI in the nighttime ionosphere. Strong neutral wind shear, steep ES plasma density gradient, and a polarized electric field are the significant factors affecting the formation of E region FAI. At mid-latitudes, joint observational experiments including ionosonde, VHF radar, Global Positioning System(GPS) stations, and all-sky optical images have revealed strong connections across different scales of ionospheric irregularities in the nighttime F region, such as spread F(SF), medium-scale traveling ionospheric disturbances(MSTID), and F region FAI.Observations suggest that different scales of ionospheric irregularities are generally attributed to the Perkins instability and subsequently excited gradient drift instability. Nighttime MSTID can further evolve into small-scale structures through a nonlinear cascade process when a steep plasma density gradient exists at the bottom of the F region. In addition, the effect of ionospheric electrodynamic coupling processes, including ionospheric E-F coupling and inter-hemispheric coupling on the generation of ionospheric irregularities, becomes more prominent due to the significant dip angle and equipotentiality of magnetic field lines in the mid-latitude ionosphere. Polarized electric fields can map to different ionospheric regions and excite plasma instabilities which form ionospheric irregularities. Nevertheless,the mapping efficiency of a polarized electric field depends on the ionospheric background and spatial scale of the field.
基金the National Natural Science Foundation of China(U1910202,21978194 and 21603256)the Natural Science Foundation of Shanxi Province(201801D121055)Program for the Shanxi Young Sanjin Scholar.
文摘With the development of coal chemical industry,large amounts of naphthalene and n-butene are produced,and converting them into high value-added products through alkylation has gained particular importance and interest.In this work,liquid coordination complexes(LCCs)were used as acid catalysts for the first time in the naphthalene alkylation reaction under mild conditions to obtain multibutylnaphthalenes with high yield.Various reaction conditions were thoroughly investigated.The LCC consisting of urea and AlCl_(3) showed excellent catalytic performance under optimal reaction conditions,giving 100%conversion of naphthalene and 99.66%selectivity towards multi-butylnaphthalenes.Combining the catalyst properties and catalytic results,a plausible reaction mechanism was proposed.The lubricating properties of the synthesized products were investigated for their potential application as lubricating base oils.The synthesized multi-butylnaphthalenes showed comparable physicochemical properties and tribological performances as the commercial cycloalkyl base oil.
基金supported by National Science and Technology Major Project(2018YFB0904000).
文摘With the increasing severity of environmental problems,many countries have set energy transition targets to promote the realization of the Paris Agreement.There has been a global consensus on utilizing solar energy resources as alternatives to conventional sources to support this energy transition.In this regard,analyzing the“location,”“quantity,”and“quality”of global solar energy resources will not only assist an individual country to efficiently utilize these resources but also promote the realization of large-scale intercontinental resource utilization and complementation.This study established the basic database,model methods,and platform tools for global solar energy assessment,Then,a global solar energy resource assessment was conducted,which included the theoretical reserves(TRs),technical installed potential capacity(TPIC),and average development cost(ADC).A comparative analysis of the assessment results for all continents was also performed.After that,based on big data analysis and geographic information system(GIS)calculations,the distribution characteristics of the global solar power TPIC were calculated with the two core indicators,namely the capacity factor and ADC.Furthermore,a data-driven quantitative evaluation of the refined development potential of solar energy resources was performed.Finally,the reasonableness and coincidence analysis of the resource assessment results were verified using data from global and specifically Chinese photovoltaic(PV)bases.
文摘Background: More and more chronic kidney disease (CKD) patients are accompanied with hyperuricaemia. As is known, hyperuricaemia is an independent hazard of both cardiovascular diseases (CVD) and chronic kidney diseases. We aim at identifying Single Nucleotide Polymorphism (SNP) difference of hURAT1 (rs7932775) and ABCG2 (rs3825016) on CKD patient with hyperuricemia and/or gout. Methods: All forty-two CKD patients were divided into two groups: hyperuricemia, and control group. 24 hours urine sample and serum were prepared for testing biochemistry parameters. The polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method is used to analyze hURAT1 and ABCG2 single nucleotide polymorphisms in different groups. Results: 17 patients have CT SNP of hURAT1 (rs7932775) and 13 patients have CT SNP of ABCG2 (rs3825016) in hyperuricemia group, while only 5 persons and 6 persons have the same mutations in control group respectively. 7 patients have CT SNP of both hURAT1 (rs7932775) and ABCG2 (rs3825016) in hyperuricemia group, while only 2 persons have the same mutations in control group. CT mutation rates of hURAT1 (rs7932775) and ABCG2 (rs3825016) in hyperuricemia group were 60.7% (17/28) and 50% (13/28) respectively, higher than that of control group (35.7% (5/14) and 42.8% (6/14)). What is more, Double SNP mutations in both hURAT1 (rs7932775) and ABCG2 (rs3825016) in hyperuricemia group were 25% (7/28), higher than that of control group (14.2%, 2/14). Conclusion: There are higher mutation rates of CT SNP in hURAT1 (rs7932775) and/or ABCG2 (rs3825016) in hyperuricemia group. We can conclude that hyperuricemia is a high risk factor in progress of CKD, which is necessary to take measures of decreasing serum uric acid to delay CKD progress.
基金the Foundation for Humanities and Social Sciences of the Chinese Ministry of Education(Grant No.:10CTQ011)China Postdoctoral Science Foundation(Grant No.:20100470971)
文摘Through investigating both users' and librarians' perceptions of the relative importance of the major criteria governing the selection of digital resources, we attempted to develop a criterion weight framework for a library's selection of digital resources, which can meet both the users' requirements and the library's goal of developing digital collections. The respective weight of each specific criterion is decided through the Analytic Hierarchy Process(AHP) Method. The findings of this study indicate that, when assigning weights to the selection criteria, it is important to consult the opinions of a wide crosssection of people, especially the views of different users. As a result, the digital resource selection system characterized by the criteria weights can reflect more comprehensively the users' requirements, and meanwhile it enables librarians' more rational selection of digital resources.
基金supported by the National Natural Science Foundation of China(No.62022027).
文摘Conversational large language models(LLMs)such as ChatGPT and GPT-4 have recently exhibited remarkable capabilities across various domains,capturing widespread attention from the public.To facilitate this line of research,in this paper,we report the development of MOSS,an open-sourced conversational LLM that contains 16 B parameters and can perform a variety of instructions in multi-turn interactions with humans.The base model of MOSS is pre-trained on large-scale unlabeled English,Chinese,and code data.To optimize the model for dialogue,we generate 1.1 M synthetic conversations based on user prompts collected through our earlier versions of the model API.We then perform preference-aware training on preference data annotated from AI feedback.Evaluation results on real-world use cases and academic benchmarks demonstrate the effectiveness of the proposed approaches.In addition,we present an effective practice to augment MOSS with several external tools.Through the development of MOSS,we have established a complete technical roadmap for large language models from pre-training,supervised fine-tuning to alignment,verifying the feasibility of chatGPT under resource-limited conditions and providing a reference for both the academic and industrial communities.Model weights and code are publicly available at https://github.com/OpenMOSS/MOSS.
基金supported by the National Natural Science Foundation of China (Nos. 22025604, 21976196, and 41877306)the Hebei Technological Innovation Center for Volatile Organic Compounds Detection and Treatment in Chemical Industry (No. ZXJJ20210403)。
文摘Mineralization of benzene,toluene,and xylene (BTX) with high efficiency at room temperature is still a challenge for the purification of indoor air.In this work,a foam Ti/Sb-Sn O2/β-Pb O_(2)anode catalyst was prepared for electrocatalytically oxidizing gaseous toluene in an all-solid cell at ambient temperature.The complex Ti/Sb-Sn O_(2)/β-Pb O_(2)anode,which was prepared by sequentially deposing Sb-Sn O_(2)and β-Pb O_(2)on a foam Ti substrate,shows high electrocatalytic oxidation efficiency of toluene (80%) at 7 hr of reaction and high CO_(2)selectivity (94.9%) under an optimized condition,i.e.,a cell voltage of 2.0 V,relative humidity of60%and a flow rate of 100 m L/min.The better catalytic performance can be ascribed to the high production rate of·OH radicals from discharging adsorbed water and the inhibition of oxygen evolution on the surface of foam Ti/Sb-Sn O_(2)/β-Pb O_(2)anode when compared with the foam Ti/Sb-Sn O_(2)anode.Our results demonstrate that prepared complex electrodes can be potentially used for electrocatalytic removal of gaseous toluene at room temperature with a good performance.
基金the National Natural Science Foundation(Nos.U1910202 and 21978194)the Key Research and Development Program of Shanxi Province(No.202102090301005)the Fund for Shanxi“1331 Project”.
文摘The chemoselective hydrogenation ofα,β-unsaturated aldehydes is a key strategy for the synthesis of fine chemicals.Herein,we developed an efficient method of depositing Pt particles on FeO_(x)/SBA-15.This strategy is dependent on using a platinumdivinyltetramethyldisiloxane complex(Pt^(0)-DVTMS)as the precursor,which we demonstrate can be removed through a H_(2)-treatment under mild conditions.This,in turn,allowed for the synthesis of catalysts with well dispersed Pt particles.The presence of FeO_(x) species also aided Pt dispersion;when coated onto SBA-15,FeO_(x) strongly interacted with dissociated Pt species,inhibiting both Pt aggregation and metal leaching.Using cinnamaldehyde as a modelα,β-unsaturated aldehyde,it was demonstrated that this catalyst was highly selective towards the unsaturated alcohol and no obvious loss in activity was observed over five recycles.This catalyst was determined to be significantly more effective than an analogous catalyst prepared using chloroplatinic acid as a precursor,evidencing the importance of using the Pt0-DVTMS precursor.We corroborate the excellent catalytic performance to highly dispersed Pt-species,whereby Pt0 and Pt^(2+) play a critical role in activating H_(2) and the C=O bond.This research demonstrates that the Pt precursor can have a significant impact on the physicochemical properties and thus,the performance of the final catalyst.It also evidences how metal support interactions can dramatically influence selectivity in such hydrogenation reactions.This novel catalyst preparation protocol,using a DVTMS ligand for Pt impregnation,offers a facile approach to the design of multi-component heterogeneous catalysts.
基金The work was supported by the National Natural Science Foundation of China (No. 10771063) and the Key Laboratory of High Performance Computation and Stochastic Iaformation Processing of Ministry of Education. The authors would like to thank the referees for their valuable suggestions.
文摘This paper is concerned with the finite element method for nonlinear Hamiltonian systems from three aspects: conservation of energy, symplicity, and the global error. To study the symplecticity of the finite element methods, we use an analytical method rather than the commonly used algebraic method. We prove optimal order of convergence at the nodes tn for mid-long time and demonstrate the symplecticity of high accuracy. The proofs depend strongly on superconvergence analysis. Numerical experiments show that the proposed method can preserve the energy very well and also can make the global trajectory error small for long time.
基金supported by the National Natural Science Foundation of China (No. 41201282)part of the Chinese National Science and Technology Support Program (2012BAD14B01/06/18)Leshan Normal University Foundation Z1159
文摘The aim of this study was to uncover ways to mitigate greenhouse gas(GHG) emissions and reduce energy consumption during the composting process. We assessed the effects of different aeration rates(0, 0.18, 0.36, and 0.54 L/(kg dry matter(dm)·min)) and methods(continuous and intermittent) on GHG emissions. Pig feces and corn stalks were mixed at a ratio of 7:1. The composting process lasted for 10 weeks, and the compost was turned approximately every 2 weeks. Results showed that both aeration rate and method significantly affected GHG emissions. Higher aeration rates increased NH3 and N2O losses,but reduced CH4 emissions. The exception is that the CH4 emission of the passive aeration treatment was lower than that of the low aeration rate treatment. Without forced aeration,the CH4 diffusion rates in the center of the piles were very low and part of the CH4 was oxidized in the surface layer. Intermittent aeration reduced NH3 and CH4 losses, but significantly increased N2 O production during the maturing periods. Intermittent aeration increased the nitrification/denitrification alternation and thus enhanced the N2 O production. Forced aeration treatments had higher GHG emission rates than the passive aeration treatment. Forced aeration accelerated the maturing process, but could not improve the quality of the end product. Compared with continuous aeration, intermittent aeration could increase the O2 supply efficiency and reduced the total GHG emission by 17.8%, and this reduction increased to 47.4% when composting was ended after 36 days.
基金This research was based on the‘Functional food research and development of Tetrastigma hemsleyanum’funded by the Shanghai Zhengyue Enterprise Management Co.,Ltd.and the Science and Technology Department of Zhejiang Province(No.2018C02045),China.
文摘Tetrastigma hemsleyanum(T.hemsleyanum)has been regarded as an anticancer food in China.However,its corresponding mechanisms remains unclear.Thus,in this study,the antitumor activity of flavones-rich fraction of root of T.hemsleyanum(FRTH)was investigated in vitro and in vivo.The results indicated that FRTH could inhibit the proliferation and migration of human hepatoellular carcinomas(HepG2)cells in vitro by the phosphatidylinositol 3-kinase/protein kinase B(PI3K/AKT)pathway.FRTH could increase the level of reactive oxygen species and change the mitochondrial membrane potential in HepG2 cells.In addition,FRTH treatment(300 mg/kg and 600 mg/kg,body weight)significantly suppressed tumor growth on HepG2 tumor-bearing nude mice.Besides,immunohistochemistry assays and western blotting revealed that FRTH enhanced the expression level of Bcl-2 associated X protein/B-cell lymphoma-2(Bax/Bcl-2),cytochrome C,caspase-3,caspase-9,and cleaved-caspase-3,and downregulated the expression level of platelet endothelial cell adhesion molecule-1(CD31),ki67,and vascular endothelial growth factor(VEGF)factor in HepG2 tumor-bearing mice.Our study suggests T.hemsleyanum as a kind of promising candidate medicine for liver cancer treatment.
基金supported by the National Natural Science Foundation of China(Nos.52070100,51978341,52081330506,and 52011530433)the Natural Science Foundation of Jiangsu Province of China(No.BK20190087)+1 种基金the Foundation of Jiangsu Collaborative Innovation Center of Biomedical Functional Materialsa project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions。
文摘Metal oxide/hydroxide-based nanocomposite adsorbents with porous supporting matrices have been recognized as efficient adsorbents for phosphorus recovery.Aiming at satisfying increasingly restrictive environmental requirements involving improving metal site utilization and lowering metal leakage risk,a glycol-solvothermal confined-space synthesis strategy was proposed for the fabrication of Fe OOH/anion exchanger nanocomposites(Fe/900s)with enhanced metal site utilization and reduced metal leakage risk.Compared to composites prepared using alkaline precipitation methods,Fe/900s performed comparably,with a high adsorption capacity of 19.05 mg-P/g with an initial concentration of 10 mg-P/L,a high adsorption selectivity of 8.2 mg-P/g in the presence of 500 mg-SO_(4)^(2-)/L,and high long-term resilience(with a capacity loss of~14%after five cycles),along with substantially lower Fe loading amount(4.11 wt.%)and Fe leakage percentage.Mechanistic investigation demonstrated that contribution of the specific Fe OOH sites to phosphate adsorption increased substantially(up to 50.97%under the optimal conditions),in which Fe(Ⅲ)-OH was the dominant efficient species.The side effects of an excessively long reaction time,which included quaternary ammonium decomposition,Fe OOH aggregation,and Fe(Ⅲ)reduction,were discussed as guidance for optimizing the synthesis strategy.The glycol-solvothermal strategy provides a facile solution to environmental problems through nanocrystal growth engineering in a confined space.