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Frontiers of Materials Science 2013年第3期7卷 227-236页

作者： li-nan zhang Zeng-Tao HOU Xin YE Zhao-Bin XU Xue-ling BAI Peng SHANG Center for Translational Medicine Research and Development Shenzhen Institutes of Advanced Technology Chinese Academy of Sciences Shenzhen 518055 China

This review investigates the current application limitations of Mg and Mg alloys. The key issues hindering the application of biodegradable Mg alloys as implants are their fast degradation rate and biological consideration. We have discussed the effect of some selected alloying element additions on the properties of the Mg-based alloy, especially the nutrient elements in human （Zn, Mn, Ca, St）. Different grain sizes, phase constituents and distributions consequently influence the mechanical properties of the Mg alloys. Solution strengthening and precipitation strengthening are enhanced by the addition of alloying elements, generally improving the mechanical properties. Besides, the hot working process can also improve the mechanical properties. Combination of different processing steps is suggested to be adopted in the fabrication of Mg-based alloys. Corrosion properties of these *** alloys have been measured in vitro and in vivo. The degradation mechanism is also discussed in terms of corrosion types, rates, by- products and response of the surrounding tissues. Moreover, the clinical response and requirements of degradable implants are presented, especially for the nutrient elements （Ca, Mn, Zn, Sr）. This review provides information related to different Mg alloying elements and presents the promising candidates for an ideal implant.

关键词： magnesium alloy alloying element corrosion biodegradation

Zeolites for the separation of ethylene,ethane,and ethyne

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Frontiers of Chemical Science and Engineering 2024年第9期18卷 137-146页

作者： Binyu Wang Qiang li Haoyang zhang Jia-nan zhang Qinhe Pan Wenfu Yan State Key Laboratory of Inorganic Synthesis&Preparative Chemistry College of ChemistryJilin UniversityChangchun 130012China Key Laboratory of Advanced Energy Catalytic and Functional Materials Preparation College of Materials Science and EngineeringZhengzhou UniversityZhengzhou 450012China Key Laboratory of Advanced Materials of Tropical Island Resources(Ministry of Education) School of Chemistry and Chemical EngineeringHainan UniversityHaikou 570228China

The cost-effective separation of ethylene(C_(2)H_(4)),ethyne(C_(2)H_(2)),and ethane(C_(2)H_(6))poses a significant challenge in the contemporary chemical *** contrast to the energy-intensive high-pressure cryogenic distillation process,zeolite-based adsorptive separation offers a low-energy *** review provides a concise overview of recent advancements in the adsorptive separation of C_(2)H_(4),C_(2)H_(2),and C_(2)H_(6)using zeolites or zeolite-based *** commences with an examination of the industrial significance of these compounds and the associated separation ***,it systematically examines the utilization of various types of zeolites with diverse cationic species in such separation *** then it explores how different zeolitic structures impact adsorption and separation capabilities,considering principles such as cation-πinteraction,π-complexation,and steric separation concerning C_(2)H_(4),C_(2)H_(2),and C_(2)H_(6)***,it discusses methods to enhance the separation performance of zeolites and zeolite-based adsorbents,encompassing structural design,modifications,and ion exchange ***,it summarizes current research trends and future directions,highlighting the potential application value of zeolitic materials in the field of C_(2)H_(4),C_(2)H_(2),and C_(2)H_(6)separation and offering recommendations for further investigation.

关键词： zeolite ethylene ethane cation-πinteraction π-complexation

Optimal geometrical configuration and oxidation state of cobalt cations in spinel oxides to promote the performance of li-O_(2) battery

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nano Research 2024年第1期17卷 221-227页

作者： Yu zhang Shuting zhang Mengwei Yuan Yufeng li Rong liu Caiyun nan Chen Chen Engineering Research Center of Advanced Rare Earth Materials Department of ChemistryTsinghua UniversityBeijing 100084China Beijing Key Laboratory of Energy Conversion and Storage Materials Institution College of ChemistryBeijing Normal UniversityBeijing 100875China X-ray diffraction Lab Analytical and Testing CenterBeijing Normal UniversityBeijing 100875China

Co_(3)O_(4) is considered as one of promising cathode catalysts for lithium oxygen(li-O_(2))batteries,which contains both tetrahedral Co^(2+)sites(Co^(2+)Td)and octahedral Co^(3+)sites(Co^(3+)Oh).It is important to reveal the effect of optimal geometric configuration and oxidation state of cobalt ion in Co_(3)O_(4) to improve the performance of li-O_(2) ***,through regulating the synthesis process,Co^(2+)and Co^(3+)sites in Co_(3)O_(4) were replaced with Zn and Al atoms to form materials with a unique Co *** li-O_(2) batteries based on ZnCo_(2)O_(4) showed longer cycle life than that of CoAl_(2)O_(4),suggesting that in Co_(3)O_(4),the Co^(3+)Oh site is a relatively better geometric configuration than Co^(2+)Td site for li-O_(2) *** calculations revealed that Co^(3+)Oh sites provide higher catalysis activity,regulating the adsorption energy of the intermediate liO_(2) and accelerating the kinetics of the reaction in batteries,which further leads to the change of the morphology of the discharge product and ultimately improves the electrochemical performance of the batteries.

关键词： lithium oxygen(li-O_(2))batteries geometrical configuration oxidation state lithium peroxide

Responses of soil stoichiometry and soil enzyme activities in the different distance around opencast coal mine of the Hulun Buir Grassland of China

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International Journal of Coal Science & Technology 2024年第1期11卷 221-231页

作者： Yinli Bi nan Guo Yanxu zhang Xianglei li Ziheng Song State Key Laboratory for Fine Exploration and Intelligent Development of Coal Resources China University of Mining and Technology(Beijing)Beijing100083China Institute of Ecological Environment Restoration in Mine Areas of West China Xi’an University of Science and TechnologyXi’an710054China

The objectives of this study were to explore the changes in soil stoichiometry and enzyme activities at different distances from an opencast coal mine in the Hulun Buir Grassland of China. Four transects were established on north and east sides of the opencast coal mining area, and samples were collected at 50 m, 550 m, and 1550 m from the pit on each transect. Control samples were collected from a grassland station 8 km from the opencast coal mining area that was not disturbed by mining. Four replicate soil samples were collected at each point on the four transects. Soil physicochemical properties and enzyme activities were determined, and correlations between soil properties and stoichiometric ratios and enzyme activities were explored using redundancy analysis. The increase in distance from mining did not significantly affect soil properties, although soil urease activity was significantly lower than that of the control area. Soil properties 1550 m from the mine pit were similar to those at the grassland control. In addition, soil total nitrogen had the greatest effect on soil stoichiometry, and soil total potassium had the greatest effect on soil enzyme activities. Coal dust from opencast mining might be the main factor affecting soil stoichiometry and enzyme activities. The results of this study provide direction for the next step in studying the influence of mining areas on soil properties and processes.

关键词： Opencast coal mine Soil stoichiometry Soil enzyme activities Distance Grassland

Ionization Engineering of Hydrogels Enables Highly Efficient Salt‑Impeded Solar Evaporation and Night‑Time Electricity Harvesting

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nano-Micro Letters 2024年第1期16卷 131-146页

作者： nan He Haonan Wang Haotian zhang Bo Jiang Dawei Tang lin li School of Energy and Power Engineering Key Laboratory of Ocean Energy Utilization and Energy Conservation of Ministry of EducationDalian University of TechnologyDalian 116024People’s Republic of China

Interfacial solar evaporation holds immense potential for brine desalination with low carbon footprints and high energy ***,as a tunable material platform from the molecular level to the macroscopic scale,have been considered the most promising candidate for solar ***,the simultaneous achievement of high evaporation efficiency and satisfactory tolerance to salt ions in brine remains a challenging scientific bottleneck,restricting the widespread ***,we report ionization engineering,which endows polymer chains of hydrogels with electronegativity for impeding salt ions and activating water molecules,fundamentally overcoming the hydrogel salt-impeded challenge and dramatically expediting water evaporating in *** sodium dodecyl benzene sulfonate-modified carbon black is chosen as the solar *** hydrogel reaches a ground-breaking evaporation rate of 2.9 kg m−2 h−1 in 20 wt%brine with 95.6%efficiency under one sun irradiation,surpassing most of the reported *** notably,such a hydrogel-based evaporator enables extracting clean water from oversaturated salt solutions and maintains durability under different high-strength deformation or a 15-day continuous ***,on the basis of the cation selectivity induced by the electronegativity,we first propose an all-day system that evaporates during the day and generates salinity-gradient electricity using waste-evaporated brine at night,anticipating pioneer a new opportunity for all-day resource-generating systems in fields of freshwater and electricity.

关键词： Solar evaporation Hydrogel evaporators Salt impeding Ionization engineering Cyclic vapor-electricity generation

Runoff and Infiltration responses of revegetated slopes to clipping management on the northern Loess Plateau

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International Soil and Water Conservation Research 2024年第1期12卷 171-183页

作者： Qilin He Binbin li Fengbao zhang nan Shen Mingyi Yang The Research Center of Soil and Water Conservation and Ecological Environment Chinese Academy of Sciences and Ministry of EducationYanglingShaanxi712100China Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water ResourcesYanglingShaanxi712100China Institute of Soil and Water Conservation Northwest A&F UniversityYanglingShaanxi712100China Water and Soil Conservation Monitoring Center of Ministry of Water Resources Beijing100053China University of Chinese Academy of Sciences Beijing100049China

Large-scale vegetation restoration can reduce local watershed water yield,limit vegetation establishment and subsequent growth,and influence regional ecosystem *** management by reducing aboveground parts of grassland was gradually recommended and adopted in Grain-for-Green project management to offset these additional ***,scientific evaluation of the effectiveness of clipping management on infiltration and runoff processes is necessary for maintaining the stability of the surface water system and the sustainability of vegetation restoration in semi-arid regions.A field simulated rainfall experiment was conducted with four managed clipping grasslands(mainly bunge needlegrass and Stipa grandis),including no clipping,light clipping,heavy clipping,and complete clipping under three slope gradients(10,20,and 30°)and three rainfall intensities(60,90,and 120 mm/h)to explore the mechanism of runoff and infiltration responses to clipping using structural equation modeling and variation partitioning based on an SCS-CN *** results showed the runoff coefficient of the light clipping,heavy clipping,and complete clipping plots were 1.33,2.22,and 4.22 times that of the no clipping *** light clipping,heavy clipping,and complete clipping plots decreased the infiltration coefficients by 0%,5%,and 26%relative to the no clipping *** intensity dominated runoff and infiltration amounts,and clipping intensity's total effect was stronger than slope *** intensity and slope gradient were more influential on runoff with increasing rainfall *** mutual inhibition effect was between clipping intensity and slope gradient on *** order to maintain the sustainability of restoration,a 25-50%vegetation coverage after clipping maximizes the benefits of increasing runoff and maintaining enough soil water supply that prevents possible soil *** propose that future vegetation restoration policies should evaluate the appropriat

关键词： Runoff Infiltration Grassland clipping management SCS-CN model Structural equation model Variation partitioning

Nitrogen-doped carbon dots-modified Prussian blue with sandwichlike structure as a high-performance electrochromic material

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nano Research 2024年第10期17卷 9174-9180页

作者： Yaqi zhang lide li Siming Zhao Yilin Ding nan Shen Yujie Sun Hao Wang Jingfa li Rufan zhang School of Chemistry and Materials Science School of Physics and Optoelectronic EngineeringNanjing University of Information Science and TechnologyNanjing 210044China Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical EngineeringTsinghua UniversityBeijing 100084China

Prussian blue(PB),as a promising inorganic electrochromic material(ECM),has been widely used in smart windows,displays,sensors,***,there are still many challenges for PB to achieve high electrochromic ***,we synthesized nitrogen-doped carbon dots-modified PB film(defined as PB@N-CDs)with a sandwich-like structure by a simple stepwise electrodeposition *** carbon dots show an obvious advantage in ultrafast electron transfer ability,which can reduce charge loss during the transfer process,improve the electrochemical activity on both sides of PB,and thus facilitate a rapid electrochromic ***,the surface of nitrogen-doped carbon dots contains multiple organic functional groups,which widen the movement path of K+ions under electrostatic ***,the PB@N-CDs film exhibits a short bleaching/coloring time(0.5/0.9 s)and a superior optical modulation range(78.6%).Particularly,the coloring efficiency has been significantly improved to 137.71 cm^(2)/C(at 700 nm).All of these results open up new avenues for developing highperformance PB-based ECMs and promoting their applications in corresponding electrochromic devices(ECDs)and smart windows.

关键词： electrochromic Prussian blue carbon dots nanostructure

UAMP-Based Delay-Doppler Channel Estimation for OTFS Systems

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China Communications 2024年第10期21卷 1-15页

作者： li Zhongjie Yuan Weijie Guo Qinghua Wu nan zhang Ji Department of Electronic and Electrical Engineering Southern University of Science and TechonologyShenzhen 518055China School of Electrical Computer and Telecommunications EngineeringUniversity of WollongongWollongongNSW 2522Australia School of Integrated Circuits and Electronics Beijing Institute of TechnologyBeijing 100081China School of Mathematics and Statistics Henan University of Science and TechnologyLuoyang 471000China

Orthogonal time frequency space(OTFS)technique, which modulates data symbols in the delayDoppler(DD) domain, presents a potential solution for supporting reliable information transmission in highmobility vehicular networks. In this paper, we study the issues of DD channel estimation for OTFS in the presence of fractional Doppler. We first propose a channel estimation algorithm with both low complexity and high accuracy based on the unitary approximate message passing(UAMP), which exploits the structured sparsity of the effective DD domain channel using hidden Markov model(HMM). The empirical state evolution(SE) analysis is then leveraged to predict the performance of our proposed algorithm. To refine the hyperparameters in the proposed algorithm,we derive the update criterion for the hyperparameters through the expectation-maximization(EM) algorithm. Finally, Our simulation results demonstrate that our proposed algorithm can achieve a significant gain over various baseline schemes.

关键词： channel estimation hidden Markov model(HMM) orthogonal time frequency space(OTFS) unitary approximate message passing(UAMP)

Fecal microbiota transplantation for treatment of non-alcoholic fatty liver disease:Mechanism,clinical evidence,and prospect

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World Journal of Gastroenterology 2024年第8期30卷 833-842页

作者： Xiao-Xia Qiu Sheng-li Cheng Yan-Hui liu Yu li Rui zhang nan-nan li Zheng li Research and Education Department Shulan(Hangzhou)Hospital Affiliated to Zhejiang Shuren University Shulan International Medical CollegeHangzhou 310022Zhejiang ProvinceChina Anhui Provincial Hospital The First Affiliated Hospital of University of Science and Technology of ChinaHefei 230000Anhui ProvinceChina Department of Clinical Pharmacy Anhui Provincial Children’s HospitalHefei 230000Anhui ProvinceChina Department of Pharmacy Taihe County People’s Hospital of Anhui ProvinceFuyang 236600Anhui ProvinceChina Department of Pharmacy The Second People’s Hospital of HefeiHefei Hospital Affiliated to Anhui Medical UniversityHefei 230000Anhui ProvinceChina University of Science and Technology of China The First Affiliated Hospital of University of Science and Technology of ChinaHefei 230001Anhui ProvinceChina Jiangsu Engineering Research Center of Cardiovascular Drugs Targeting Endothelial Cells College of Health SciencesSchool of Life SciencesJiangsu Normal UniversityXuzhou 221000Jiangsu ProvinceChina

The population of non-alcoholic fatty liver disease(NAFLD)patients along with relevant advanced liver disease is projected to continue growing,because currently no medications are approved for *** microbiota transplantation(FMT)is believed a novel and promising therapeutic approach based on the concept of the gut-liver axis in liver *** has been an increase in the number of pre-clinical and clinical studies evaluating FMT in NAFLD treatment,however,existing findings diverge on its ***,we briefly summarized the mechanism of FMT for NAFLD treatment,reviewed randomized controlled trials for evaluating its efficacy in NAFLD,and proposed the prospect of future trials on FMT.

关键词： Non-alcoholic fatty liver disease Fecal microbiota transplantation Randomized controlled trial Mechanism Efficacy

Effects of biochanin A on lactational performance,nitrogen metabolism,and blood metabolites in dairy cows

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Animal Nutrition 2024年第3期18卷 441-449页

作者： Zhanbo Xiong Yanjun li Xiaoyin zhang Shiqi zhang Kexin li nan Zheng Shengguo Zhao Jiaqi Wang State Key Laboratory of Animal Nutrition Institute of Animal SciencesChinese Academy of Agricultural SciencesBeijing 100193China

Optimizing nitrogen utilization efficiency and mitigating nitrogen losses in cows plays a pivotal role in fostering economic sustainability within contemporary agricultural *** A(BCA),a natural component in red clover,has the potential to improve nitrogen metabolism in dairy *** primary objective of this study was to probe the impact of biochanin A supplementation on lactational performance,nitrogen metabolism,and blood metabolites in dairy cows.A complete randomized block design experiment was conducted over 28 d,involving 36 multiparous Holstein cows(comparable milk yield=37.1±2.90 kg,BW=642±70.0 kg,days in milk=92±8.0 d,and parity=2.4±0.50),which were allocated to three treatment groups:the Control group(with 0 g/d BCA),the Low group(with 10 g/d per cow BCA),and the High group(with 40 g/d per cow BCA).Biochanin A supplementation improved the lactational performance of cows by increasing milk yield by 6.3%(P=0.007)and feed efficiency by 12.7%(P=0.009).Total intestinal apparent digestibility was unaffected by BCA supplementation(P>0.05),but microbial nitrogen was increased by 30.0%(P=0.002)for promoting nitrogen utilization efficiency by 20.7%(P=0.004).Milk competent yields(protein,lactose,and non-fat milk solid)were increased with increasing BCA supplementation(P 0.05).BCA did not affect body health of dairy ***,none of the plasma endocrine hormones were affected(P>0.05).A total of 95 significantly different metabolites were screened from the plasma metabolites of cows in the BCA-added and non-added *** performing an enrichment analysis of the metabolic pathways associated with the different metabolites,six specific pathways were identified:bile acid biosynthesis,aspartate metabolism,pyrimidine metabolism,arginine and proline metabolism,the urea cycle,and ammonia *** inclusion of BCA is suggested to enhance milk yield and modulate nitrogen metabolism by influencing relevant metabolites within the metabolic pathwa

关键词： Biochanin A Lactational performance Nutritional metabolism Blood metabolite