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Cementing properties of steel slag activated by sodium silicates and sodium hydroxide

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Journal of University of Science and Technology Beijing 2005年第5期12卷 464-468页

作者： Wen Ni en wang Jianping li Han Sun Civil and environmental engineering School University of Science and Technology Beijing Beijing 100083 China

Steel slag which is mainly composed of γ-Ca2SiO4 and other silicates or alumino-silicates is activated by sodium sificates and sodium hydroxide. The powders of such steel slag are usually inert to hydrate and subsequently have very low ability of cementing. But when sodium silicates and sodium hydroxide are used as activators the steel slag shows very good properties of cementing. When activated with NaOH solution the hardened slurry of the steel slag has a compressive strength of 11.13 MPa after being cured for 28 days. When activated with Na2SiO3 solution the samples after being cured for 28 days have an average compres- sive strength of 40.23 MPa. While the steel slag slurry which is only mixed with water has a compressive of 0.88 MPa after being cured for 28 days.

关键词： steel slag sodium silicate sodium hydroxide cement binding material

Soil Carbon Sequestration Potential as Affected by Management Practices in Northern China:A Simulation Study

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Pedosphere 2014年第4期24卷 529-543页

作者： wang Guo-Cheng wang en-li HUANG Yao XU Jing-Jing State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry(LAPC) Institute of Atmospheric PhysicsChinese Academy of Sciences CSIRO Land & Water Black MountainCanberraACT 2601(Australia) State Key Laboratory of Vegetation and environmental Change(LVEC) Institute of BotanyChinese Academy of Sciences

Soil has been identified as a possible carbon （C） sink for sequestering atmospheric carbon dioxide （CO2）. However, soil organic carbon （SOC） dynamics in agro-ecosystems is affected by complex interactions of various factors including climate, soil and agricultural management practices, which hinders our understanding of the underlying mechanisms. The objectives of this study were to use the Agricultural Production Systems simulator （APSIM） model to simulate the long-term SOC dynamics under different management practices at four long-term experimental sites, Zhengzhou and Xuzhou with double cropping systems and Gongzhuling and Urtimqi with single cropping systems, located in northern China. Firstly, the model was calibrated using information from the sites and literature, and its performance to predict crop growth and SOC dynamics was examined. The calibrated model was then used to assess the impacts of different management practices, including fertilizer application, irrigation, and residue retention, on C dynamics in the top 30 cm of the soil by scenario modelling. Results indicate a significant SOC sequestration potential through improved management practices of nitrogen （N） fertilizer application, stubble retention, and irrigation. Optimal N fertilization （Nopt） and 100% stubble retention （R100） increased SOC by about 11.2%, 208.29%, and 283.67% under irrigation at Gongzhuling, Zhengzhou, and Xuzhou, respectively. Soil organic carbon decreased rapidly at lJriimqi under irrigation, which was due to the enhanced decomposition by increased soil moisture. Under rainfed condition, SOC remained at a higher level. The combination of Nopt and R100 increased SOC by about 0.46% under rainfed condition at /Jr/imqi. Generally, agricultural soils with double cropping systems （Zhengzhou and Xuzhou） showed a greater potential to sequester C than those with single cropping systems （Gongzhuling and Urumqi）.

关键词： agro-ecosystems APSIM model fertilizer application irrigation residue retention scenario analysis soil organic carbon

Contrasting Effects of Agricultural Management on Soil Organic Carbon Balance in Different Agricultural Regions of China

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Pedosphere 2013年第6期23卷 717-728页

作者： wang Guo-Cheng LUO Zhong-Kui wang en-li HUANG Yao State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of Sciences CSIRO Land & Water Black Mountain State Key Laboratory of Vegetation and environmental Change Institute of BotanyChinese Academy of Sciences

Improving management of soil organic carbon(SOC)has been considered as a substantial mitigation strategy to climate *** such as stubble retention(SR),conservation tillage(ZT),and fertilization are recommended for both promoting production and accumulating ***,whether such management practices can cause net increase in SOC or just a slow-down of SOC decline largely depends on the current status of SOC for a given *** paper synthesized the available SOC data in the croplands of China,and analysed the change of SOC in the top 20 cm soil as a result of management *** results showed that,on average,SOC increased by 18.3%through SR,by 9.1%through ZT,and by 12.4%,36.9%and 41.5%through application of inorganic(IF),organic(OF)and combined inorganic and organic fertilizers(IOF),respectively,compared to those under stubble removal,conventional tillage and no *** SR,ZT,IF,OF and IOF,SOC increased by 16.0%,10.2%,8.2%,32.2%and41.3%,respectively,at the end of the trials compared with the initial values at the start of the *** analysis also showed that in Northeast and Northwest China,SOC in agricultural soils is still decreasing due to *** North and South China,however,SOC appears to have reached a new equilibrium of low SOC state after a long cultivation history,and soils have greater potential to sequester *** analysis highlights the need of taking account of the baseline status to assess the net soil C balance over time and space.

关键词： agricultural practices climate change fertilization residue management tillage

Spatiotemporal Changes in Soil Nutrients:A Case Study in Taihu Region of China

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Journal of Integrative Agriculture 2014年第1期13卷 187-194页

作者： liU Lei-lei ZHU Yan liU Xiao-jun CAO Wei-xing XU Mao wang Xu-kui wang en-li National engineering and Technology Center for Information Agriculture/Jiangsu Key Laboratory for Information Agriculture/Nanjing Agricultural University Soil and Fertilizer Station of Jiangsu Agricultural Department CSRIO Sustainable Agricultural Flagship CSIRO Land and Water

The accurate assessment of the spatiotemporal changes in soil nutrients influenced by agricultural production provides the basis for development of management strategies to maintain soil fertility and balance soil nutrients. In this paper, we combined spatial measurements from 2 157 soil samples and geostatistical analysis to assess the spatiotemporal changes in soil organic carbon （SOC）, total nitrogen （TN）, available phosphorus （AP） and available potassium content （AK） from the first soil survey （in the 1980s） to the second soil survey （in the 2000s） in the Taihu region of Jiangsu Province in China. The results showed that average soil nutrients in three soil types all exhibited the increased levels in the 2000s （except for AK in the yellow brown soil）. The standard deviation of soil nutrient contents increased （except for TN in the paddy soil）. Agricultural production in the 20 years led to increases in SOC, TN, AP and AK by 74, 82, 89 and 65%, respectively, of the Taihu areas analyzed. From the 1980s to 2000s all the nugget/sill ratios of soil nutrients indices were between 25 and 75% （except for AK in the yellow brown soil in the 2000s）, indicating moderate spatial dependence. The ratio of AP in the yellow brown soil in the 2000s was 88.74%, showing weak spatial dependence. The spatial correlation range values for SOC, TN, AP and AK in the 2000s all decreased. The main areas showing declines in SOC, TN and AP were in the northwest. For AK, the main region with declining levels was in the east and middle of western areas. Apparently, the increase in soil nutrients in the Taihu region can be mainly attributed to the large increase in fertilizer inputs, change in crop systems and enhanced residues management since the 1980s. Future emphasis should be placed on avoiding excess fertilizer inputs and balancing the effects of the fertilizers in soils.

关键词： soil fertility spatiotemporal variability soil organic carbon total nitrogen phosphorus potassium

Reaction Mechanism of Actin ATP Hydrolysis Studied by QM/MM Calculations

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Chemical Research in Chinese Universities 2024年第5期40卷 849-855页

作者： wang Yiwen liN lirui XU li-Yan li en-Min DONG Geng Department of Biochemistry and Molecular Biology Shantou University Medical CollegeShantou515041P.R.China Department of Bioinformatics Shantou University Medical CollegeShantou515041P.R.China Medical Informatics Research Center Shantou University Medical CollegeShantou515041P.R.China Key Laboratory of Molecular Biology in High Cancer Incidence Coastal Area of Guangdong Higher Education Institutes Shantou University Medical CollegeShantou515041P.R.China Cancer Research Center Shantou University Medical CollegeShantou515041P.R.China Guangdong Provincial Key Laboratory of Infectious Diseases and Molecular Immunopathology Shantou University Medical CollegeShantou515041P.R.China

Actin fibers are an important part of the cytoskeleton,providing vital support for the plasma *** function is driven by its ATPase(ATP:adenosine triphosphate)activity,i.e.,ATP+H_(2)O→ADP+*** seemingly simple reaction has attracted much attention because the hydrolysis of ATP provides energy to support life ***,the reaction mechanism of ATP hydrolysis in actin is not *** order to gain deep insights into the functions of actin,it is essential to elucidate the reaction mechanism of the actin ATP *** this paper,we have studied the reaction mechanism of the ATP hydrolysis in actin by the combined quantum mechanical and molecular mechanics(QM/MM)*** results show that 1)bond cleavage of the Pγ—OS of ATP and bond formation between oxygen of the lytic water and Pγatoms take place simultaneously,and this is the rate-limiting step of the hydrolysis;2)the proton on the lytic water transfers to the phosphate to form H_(2)P_(γ)O_(4)−via one bridge *** energy barrier of the complete reaction is 17.6 kcal/mol(1 kcal=4.184 kJ),which is in high agreement with the experimental value.

关键词： Actin Adenosine triphosphate(ATP)hydrolysis Quantum mechanical and molecular mechanics(QM/MM) Reaction mechanism

ZIF-8 modified by isocyanate as a photocatalytic antibacterial agent

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Rare Metals 2024年第6期43卷 2708-2718页

作者： Yi-Ning Zhang Zhen Pei Zi-Hao wang Chong-en wang Fen-Fen liang li-Qiao Wei College of Architecture Taiyuan University of TechnologyTaiyuan 030024China Key Laboratory of Interface Science and engineering in Advanced Materials of Taiyuan University of Technology Ministry of EducationTaiyuan 030024China Department of Materials Science and engineering Shanxi Institute of TechnologyYangquan 045000China Shanxi-Zheda Institute of Advanced Materials and Chemical engineering Taiyuan 030000China

Zeolite imidazole skeleton(ZIF-8)is a promising option for self-cleaning of building exterior walls due to its large specific surface area,high antibacterial activity and low ***,it suffers from low antibacterial efficiency and yield under visible light *** address the issues,we developed the photocatalytic materials T-ZIF-8-TDI(thermally treated-ZIF-8-toluene 2,4-diisocyanate)by modifying ZIF-8 with thermal oxygen sensitization and chemical *** results show that the yield of T-ZIF-8-TDI photocatalytic antibacterial agent is increased to 11.5 times of that of T-ZIF-8,while maintaining the crystal structure of T-ZIF-8 and thermal stability up to 60℃.Furthermore,T-ZIF-8-TDI exhibits extended optical response range to the nearinfrared region,significantly narrowed band gap,improved photogenerated elec tron-hole separation efficiency,reduced recombination rate,and excellent photocatalytic *** the concentration of antibacterial agent is 600 mg·L^(-1),the antibacterial rate of Escherichia coli(***)reaches 99.99%irradiated by visible light for30 min,and when the concentration of antibacterial agent is 200 mg·L^(-1),the antibacterial rate of Staphylococcus aureus(***)reaches 99.99%irradiated by visible light for 25 *** also analyzed the reasons in detail from the aspects of bacterial species and antibacterial mechanism,and proposed the antibacterial mechanism of·O_(2)^(-)and h^(+)as the main active *** findings suggest that T-ZIF-8-TDI photocatalytic antibacterial agent has potential for use in self-cleaning of building exterior walls.

关键词： ZIF-8 Hot oxygen sensitization Modified by isocyanate Antimicrobial performance Photocatalytic antibacterial mechanism

Melt flow,heat transfer and solidification in a flexible thin slab continuous casting mold with vertical-combined electromagnetic braking

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Journal of Iron and Steel Research International 2024年第2期31卷 401-415页

作者： lin Xu Ze-feng Han Christian Karcher en-gang wang Key Laboratory of Electromagnetic Processing of Materials(Ministry of Education) Northeastern UniversityShenyang110819LiaoningChina Key Laboratory of liaoning Province for Clean Combustion Power Generation and Heating Technology Shenyang Institute of EngineeringShenyang110136LiaoningChina Institute of Thermodynamics and Fluid Mechanics Technische Universität IlmenauIlmenau98684Germany

During continuous casting of steel slabs,the application of electromagnetic braking technology(EMBr)provides an effective tool to influence solidification by controlling the pattern of melt flow in the ***,the quality of the final product can be improved considerably.A new electromagnetic braking(EMBr)method,named vertical-combined electromagnetic braking(VC-EMBr),is proposed to be applied to a flexible thin slab casting(FTSC)*** evaluate the beneficial effects of the VC-EMBr,the melt flow,heat transfer,and solidification processes in the FTSC mold are studied by means of numerical *** detail,a Reynolds-averaged Navier–Stokes turbulence model together with an enthalpy-porosity approach was *** numerical findings are compared with respective simulations using the traditional *** results demonstrate that the application of the VC-EMBr contributes significantly to preventing relative slab *** contrast to the Ruler-EMBr,the additional vertical magnetic poles of the VC-EMBr preferentially suppress the direct impact of jet flow on the narrow face of FSTC mold and considerably diminish the level fluctuation near the meniscus *** instance,by applying a magnetic flux density of 0.3 T,the maximum amplitude of meniscus deflection reduces by about 80%.Moreover,the braking effect of the VC-EMBr effectively improves the homogeneity of temperature distribution in the upper recirculation region and increases the solidified shell thickness along the casting *** this basis,the newly proposed VC-EMBr shows a beneficial effect in preventing relative slab defects for FTSC thin slab continuous casting.

关键词： Electromagnetic braking Mold Melt flow Heat transfer Solidification

Global research trends and hotspots in overweight/obese comorbid with depression among children and adolescents: A bibliometric analysis

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World Journal of Psychiatry 2024年第8期14卷 1267-1284页

作者： Ya-Qi wang Tao-Tao Wu Yan li Shi-en Cui Ying-Shuai li College of Basic Medical Sciences Zhejiang Chinese Medical UniversityHangzhou 310051Zhejiang ProvinceChina National Institute of Traditional Chinese Medicine Constitution and Preventive Treatment of Diseases Beijing University of Chinese MedicineBeijing 100029China

BACKGROUND Overweight/obesity combined with depression among children and adolescents(ODCA)is a global *** bidirectional relationship between depression and overweight/obesity often leads to their *** and adolescence represent critical periods for physical and psychological development,during which the comorbidity of overweight/obesity and depression may increase the risk of adverse health *** To evaluate the relationship between ODCA,we conduct a bibliometric analysis to aid in formulating prevention and treatment *** From 2004 to 2023,articles related to ODCA were selected using the Science Citation Index Expanded from the Web of Science Core *** analysis of relevant publications,including countries/regions,institutions,authors,journals,references,and keywords,was conducted using the online bibliometric analysis platforms,CiteSpace,VOSviewer,and *** Between 2004 and 2023,a total of 1573 articles were published on *** United States has made leading contributions in this field,with Harvard University emerging as the leading contributor in terms of research output,and Tanofsky being the most prolific *** J Adolescent Health has shown significant activity in this *** on the results of the keyword and reference analyses,inequality,adverse childhood experiences,and comorbidities have become hot topics in ***,the impact of balancedrelated behavior and exploration of the biological mechanisms,including the potential role of key adipocytokines and lipokines,as well as inflammation in ODCA,have emerged as frontier *** The trend of a significant increase in ODCA publications is expected to *** research findings will contribute to elucidating the pathogenic mechanisms of ODCA and its prevention and treatment.

关键词： Children Adolescents Overweight Obesity Depression Bibliometric analysis Research trends

The Perturbed Compound Poisson Risk Model with Proportional Investment

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 109-128页

作者： Nai-dan Deng Chun-wei wang Jia-en Xu School of Mathematics and Statistics Henan University of Science and TechnologyLuoyang471023China

In this paper, the insurance company considers venture capital and risk-free investment in a constant proportion. The surplus process is perturbed by diffusion. At first, the integro-differential equations satisfied by the expected discounted dividend payments and the Gerber-Shiu function are derived. Then, the approximate solutions of the integro-differential equations are obtained through the sinc method. Finally, the numerical examples are given when the claim sizes follow different distributions. Furthermore, the errors between the explicit solution and the numerical solution are discussed in a special case.

关键词： expected discounted dividend payments lognormal distribution proportional investment perturbed risk model sinc numerical method