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Journal of Environmental Sciences 2006年第4期18卷 708-715页

作者： CHEN Ren-sheng KANG Er-si JI Xi-bin yang jian-ping zhang Zhi-hui yang Yong Laboratory of Watershed Hydrology and Ecology Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy ofSciences Lanzhou 730000 China

Atmospheric CO2 concentration （CC） near land surface and meteorological variables have been measured at four sites, named Yeniugou （alpine meadow and permafrost）, Xishui （mountainous forest）, Linze （oasis edge） and Ejina （lower desert）, respectively, in Heihe River Basin, northwest China. The results showed that, the half hourly CC at night was larger than in daytime, and the daily averaged CC was the largest in winter. The averaged CC of 932 d at the Linze was about 418 ppm, was about 366 ppm in the 762 d at the Ejina. In the same period from September 23 to November 9, 2004, the averaged CC was about 625,334, 436 and 353 ppm, at Yeniugou, Xishui, Linze and Ejina, respectively. The linear relationship between daily averaged CC and air temperature T was negative, between CC and relative humidity （RH） was positive. The linear CC-atmospheric pressure （A P） relationship was negative at the Linze and Yeniugou, was positive at the Ejina. The relationship between CC and global radiation R was exponent, and soil temperature Ts was negative linear, and soil water content was complex. The correlation between CC and wind speed was not existent. Using meteorological variables together to simulate CC, could give good results.

关键词： CO2 concentration meteorological variables Heihe River Basin

Microstructure evolutions and interfacial bonding behavior of Ni-based superalloys during solid state plastic deformation bonding

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Journal of Materials Science & Technology 2020年第11期42卷 1-11页

作者： jian yang zhang Bin Xu Naeemul Haq Tariq MingYue Sun DianZhong Li Yi Yi Li Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Department of Metallurgy and Materials Engineering Pakistan Institute of Engineering and Applied SciencesNiloreIslamabadPakistan

As an advanced solid state bonding process,plastic deformation bonding(PDB)is a highly reliable metallurgical joining method that produces significant plastic deformation at the bonding interface of welded joints through thermo-mechanical *** this study,PDB behavior of IN718 superalloy was systematically investigated by performing a series of isothermal compression tests at various processing *** was revealed that new grains evolved in the bonding area through discontinuous dynamic recrystallization(DDRX)at 1000–1150℃.Electron backscattered diffraction(EBSD)and transmission electron microscopy(TEM)results revealed that the bonding of joints is related with interfacial grain boundary(IGB)bulging process,which is considered as a nucleation process of DRXed grain under different deformation *** recrystallization process,the bonded interface moved due to strain-induced boundary migration(SIBM)*** energy difference(caused by accumulation of dislocations at the bonding interface)was the dominant factor for SIBM during *** mechanical properties of the bonded joints were dependent upon the recrystallized microstructure and SIBM ensued during PDB.

关键词： Isothermal compression bondingDynamic recrystallization Microstructures Grain boundary Misorientation

Global Exponential Stability of a Class of Neural Networks with Delays

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Acta Mathematicae Applicatae Sinica 2009年第1期25卷 43-50页

作者： Feng-jian yang Chao-long zhang Chuan-yong Chen Xin-ming Chen Department of Computational Science Zhongkai University of Agriculture and Engineering Guangzhou 510225China

This paper is concerned with the stability of neural networks with time-varying delays. Under assumption that the nonlinear stimulate functions are Lipschitz continuous, by means of generalized Halanay inequalities, Dini＇s derivative and functional analysis techniques, several globally exponential stability criteria are established, which are only dependent on the parameters of the system.

关键词： Neural network Halanay's inequality delay globally exponential stability

Effect of strain rate on plastic deformation bonding behavior of Ni-based superalloys

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Journal of Materials Science & Technology 2020年第5期40卷 54-63页

作者： jian yang zhang Bin Xu Naeem ul Haq Tariq Ming Yue Sun Dian Zhong Li Yi Yi Li Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang110016China Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang110016China Department of Metallurgy and Materials Engineering Pakistan Institute of Engineering and Applied SciencesNiloreIslamabadPakistan

Plastic deformation bonding(PDB)has emerged as a promising solid state bonding technique with limited risk of phase transformations and residual thermal stresses in the *** this study,the PDB behavior of IN718 superalloy was systematically investigated by performing a series of isothermal compression tests at various processing *** was revealed that,with increasing PDB strain rate at 1000?C,different extents of dynamic recrystallization(DRX)occur in the bonding area of IN718 *** extent of DRX,average size of DRXed grains,and a newly proposed"interfacial bonding ratio(?Bonding)"parameter(to quantify the bond quality)were initially reduced with increase in the strain rate up to 0.1 s-1 and later increased at further higher strain *** backscattered diffraction(EBSD)and transmission electron microscopy(TEM)based interfacial microstructure analyses indicated that the quality of the bonded joints is closely related with the development of fine DRXed grains at the bonding interface with the increasing strain,which promotes adiabatic temperature *** was revealed that the initial bulging and subsequent migration of the original interfacial grain boundary(IGB)were the main mechanisms promoting DRX in the well bonded IN718 superalloy ***,the mechanical properties of the bonded joints were not only controlled by the recrystallized microstructure but also depended upon the Bonding parameter of the joints.

关键词： Inconel 718 superalloy Isothermal compression bonding Dynamic recrystallization Grain boundary Subgrain Strain rate

An improved formula for standard hypoxia tolerance time to evaluate hypoxic tolerance in mice

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Military Medical Research 2019年第2期6卷 111-116页

作者： Gang Xu Yu-Qi Gao Yi-Xing Gao Gang Wu jian-yang zhang Wen-Xiang Gao Institute of Medicine and Hygienic Equipment for High Altitude Region College of High Altitude Military MedicineArmy Medical University(Third Military Medical University)Chongqing400038China Key Laboratory of High Altitude Medicine People’s Liberation ArmyChongqing400038China

Background: Hypoxia is a primary cause of mountain sickness and a common pathological condition in patients with heart failure, shock, stroke, and chronic obstructive pulmonary disease(COPD). Thus far, little advancement in countering hypoxic damage has been achieved, and one of the main reasons is the absence of an ideal algorithm or calculation method to normalize hypoxia tolerance scores when evaluating an animal model. In this study, we improved a traditional calculation formula for assessment of hypoxia ***: We used a sealed bottle model in which the oxygen is gradually consumed by a mouse inside. To evaluate the hypoxia tolerance of mice, the survival time(ST) of the mouse is recorded and was used to calculate standard hypoxia tolerance time(STT) and adjusted standard hypoxia tolerance time(ASTT). Mice administered with methazolamide and saline were used as positive and negative controls, ***: Since mice were grouped according to either body weight(BW) or bottle volume, we found a strongly negative correlation between STT and BW instead of between STT and bottle volume, suggesting that different BWs could cause false positive or negative errors in the STT results. Furthermore, both false positive and negative errors could be rectified when ASTT was used as the evaluation index. Screening for anti-hypoxic medicines by using mice as the experimental subjects would provide more credible results with the improved ASTT method than with the STT ***: ASTT could be a better index than STT for the evaluation of hypoxia tolerance abilities as it could eliminate the impact of animal BW.

关键词： Hypoxia Standard hypoxic tolerance time Mice model Body weight

DL-3-n-butylphthalide improved physical and learning and memory performance of rodents exposed to acute and chronic hypobaric hypoxia

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Military Medical Research 2022年第1期9卷 1-11页

作者： Gang Xu Yi-Kun Shi Bin-Da Sun Lu Liu Guo-Ji E Shu He jian-yang zhang Bao Liu Qiu Hu jian Chen Yu-Qi Gao Er-Long zhang Institute of Medicine and Equipment for High Altitude Region College of High Altitude Military MedicineArmy Medical UniversityChongqing 400038China Key Laboratory of Extreme Environmental Medicine Ministry of Education of ChinaChongqing 400038China Key Laboratory of High Altitude Medicine People's Liberation ArmyChongqing 400038China

Background:Studies have revealed the protective effect of DL-3-n-butylphthalide(NBP)against diseases associated with ischemic ***,the role of NBP in animals with hypobaric hypoxia has not been *** study investigated the effects of NBP on rodents with acute and chronic hypobaric ***:Sprague-Dwaley rats and Kunming mice administered with NBP(0,60,120,and 240 mg/kg for rats and 0,90,180,and 360 mg/kg for mice)were placed in a hypobaric hypoxia chamber at 10,000 m and the survival percentages at 30 min were ***,the time and distance to exhaustion of drug-treated rodents were evaluated during treadmill running and motor-driven wheel-track treadmill experiments,conducted at 5800 m for 3 days or 20 days,to evaluate changes in physical *** frequency of active escapes and duration of active escapes were also determined for rats in a shuttle-box experiment,conducted at 5800 m for 6 days or 27 days,to evaluate changes in learning and memory *** levels were measured in the gastrocnemius muscle and malonaldehyde(MDA),superoxide dismutase(SOD),hydrogen peroxide(H_(2)O_(2)),glutathione peroxidase(GSH-Px),and lactate were detected in sera of rats,and routine blood tests were also ***:Survival analysis at 10,000 m indicated NBP could improve hypoxia tolerance *** time and distance to exhaustion for mice(NBP,90 mg/kg)and time to exhaustion for rats(NBP,120 and 240 mg/kg)significantly increased under conditions of acute hypoxia compared with control *** treatment also significantly increased the time to exhaustion for rats when exposed to chronic ***,240 mg/kg NBP significantly increased the frequency of active escapes under conditions of acute ***,the levels of MDA and H_(2)O_(2) decreased but those of SOD and GSH-Px in the sera of rats increased under conditions of acute and chronic ***,ATP levels in the gastrocnemius muscle significantly incre

关键词： DL-3-n-butylphthalide Hypobaric hypoxia Physical function Learning and memory function Oxidative stress Energy metabolism

Transforming waste particles into valuable adsorbents via amyloid-mediated molecular engineering

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Science China Chemistry 2025年第1期68卷 317-328页

作者： Qingmin yang jian Zhao Yujia zhang Xingyu Zhou Hao Ren Bowen Hu Zhongli Lei Lixin Chen Peng yang School of Material and Chemical Engineering Bengbu University Anhui Provincial Engineering Laboratory of Silicon-Based Materials School of Chemistry and Chemical Engineering Northwestern Polytechnical University Key Laboratory of Applied Surface and Colloid Chemistry Ministry of Education School of Chemistry and Chemical EngineeringShaanxi Normal University Xi'an Key Laboratory of Polymeric Soft Matter School of Chemistry and Chemical Engineering Shaanxi Normal University International Joint Research Center on Functional Fiber and Soft Smart Textile School of Chemistry and Chemical EngineeringShaanxi Normal University

The high-value utilization of industrial solid waste using a facile and eco-friendly process is of great interest and significance in reducing environmental pollution and developing a green circular economy. Herein, we propose an amyloid-mediated molecular engineering strategy to transform particulate waste into valuable adsorbents for metal ions. Our method has the advantage of aqueous solution fabrication under mild conditions without the use of high-temperature hydrothermal methods and toxic chemical reagents. Amyloid-mediated molecular engineering manipulates the phase transition of bovine serum albumin(BSA)on particulate waste surfaces, resulting in a remarkable ～3.1 times improvement in the adsorption capacity of fly ash, a typical industrial solid waste for gold ions after modification with the phase-transitioned BSA(PTB). The resultant adsorption ability was 69–1,980 times higher than those of conventional and emerging adsorbent materials such as ion exchange resins, activated carbon(AC), covalent organic frameworks(COFs), and metal-organic frameworks(MOFs). We further demonstrated the application of our PTB-modified materials in the recovery of precious metals from low-grade gold ore and electronic waste leachates. Consequently, this strategy could increase the value of waste materials nearly 27 times. In addition, this method is generally extendable to other conventional industrial adsorbents such as resin, clay, and Al2O3, and enhances their adsorption capabilities at least twofold. Overall, this work provides a simple and green approach for improving the adsorption performance of solid particles, and is expected to develop into a universal strategy for transforming waste particles into high-value-added products.

关键词： amyloid-like protein aggregates surface engineering fly ash solid waste adsorption

The interactive effects of nitrogen addition and increased precipitation on gross ecosystem productivity in an alpine meadow

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Journal of Plant Ecology 2022年第1期15卷 168-179页

作者： Ruo-Nan Shen yang-jian zhang Jun-Tao Zhu Ning Chen Yao Chen Guang Zhao Yi-Xuan Zhu Ze Tang Wen-Yu Li Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Lhasa Plateau Ecosystem Research Station Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun 130102China

The ecological consequences of precipitation change and increased atmospheric nitrogen(N)deposition have profound impacts on ecosystem CO2 exchange in grassland *** and N can largely influence grassland productivity,community composition and ecosystem ***,the influences of water and N addition on the ecosystem CO2 exchange of alpine grassland ecosystems remain unclear.A field manipulative experiment with water and N additions was conducted in an alpine meadow on the Tibetan Plateau over 4 years with contrasting precipitation *** were four treatments:control(Ctrl),N addition(N),water addition(W)and N and water addition(NW),each replicated three times.N addition,but not water addition,increased gross ecosystem productivity(GEP),plant biomass,community cover and community-weighted mean *** responses of ecosystem CO2 exchange to water and N addition varied between the wet and dry *** addition had a positive effect on net ecosystem carbon exchange(NEE)due to a larger increase in GEP than in ecosystem respiration(ER)only in the dry *** the contrary,N addition significantly enhanced ecosystem CO2 exchange only in the wet *** increased GEP in N addition was attributed to the larger increase in NEE than ***,N addition stimulated NEE mainly through increasing the cover of dominant *** observations highlight the important roles of precipitation and dominant species in regulating ecosystem CO2 exchange response to global environmental change in alpine grasslands.

关键词： ecosystem CO2 exchange water addition nitrogen addition plant functional groups alpine grassland

Structural designs and mechanism insights into electrocatalytic oxidation of 5-hydroxymethylfurfural

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Journal of Energy Chemistry 2025年第1期100卷 792-814页

作者： Jing Lei Huijie zhang jian yang Jia Ran Jiqiang Ning Haiyan Wang Yong Hu Key Laboratory of the Ministry of Education for Advanced Catalysis Materials Department of Chemistry Zhejiang Normal University Jinhua Advanced Research Institute Department of Optical Science and Engineering Fudan University College of Chemistry and Materials Engineering Zhejiang A&F University

Biomass conversion offers an efficient approach to alleviate the energy and environmental *** oxidation of 5-hydroxymethylfurfural(HMF) has attracted tremendous attention in the latest few years for the mild synthesis conditions and high conversion efficiency to obtain 2,5-furan dicarboxylic acid(FDCA), but there still remain problems such as limited yield, short cycle life,and ambiguous reaction mechanism. Despite many reviews highlighting a variety of electrocatalysts for electrochemical oxidation of HMF, a detailed discussion of the structural modulation of catalyst and the underlying catalytic mechanism is still lacking. We herein provide a comprehensive summary of the recent development of electrochemical oxidation of HMF to FDCA, particularly focusing on the mechanism studies as well as the advanced strategies developed to regulate the structure and optimize the performance of the electrocatalysts, including heterointerface construction, defect engineering,single-atom engineering, and in situ reconstruction. Experimental characterization techniques and theoretical calculation methods for mechanism and active site studies are elaborated, and challenges and future directions of electrochemical oxidation of HMF are also prospected. This review will provide guidance for designing advanced catalysts and deepening the understanding of the reaction mechanism beneath electrochemical oxidation of HMF to FDCA.

关键词： Structural design

Long term clinical outcomes in patients with moderate renal insufficiency undergoing stent based percutaneous coronary intervention

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Chinese Medical Journal 2006年第14期119卷 1176-1181页

作者： zhang Rui-yan NI Jing-wei zhang jian-sheng HU jian yang Zhen-kun zhang Qi LUE An-kang SHEN Wei-feng Department of Cardiology Shanghai Ruijin Hospital School of Medicine Shanghai Jiao Tong University Shanghai 200025

Background Patients with end-stage renal disease have a high mortality from coronary artery disease, but the impact of moderate renal insufficiency on clinical outcomes after percutaneous coronary intervention （PCI） and the effect of drug-eluting stent implantation in these patients remain unclear. This study determined the long-term effect of moderate renal insufficiency on death and major adverse cardiac events （MACE） after stent based PCI and examined whether drug-eluting stent implantation could favourably influence clinical outcome. Methods Major adverse cardiac events and causes of mortality were determined for 1012 patients undergoing percutaneous intervention from January 1, 2002 to December 31, 2004 at Shanghai Ruijin Hospital. Based on estimated creatinine clearance levels, long term outcomes were compared between patients with estimated creatinine clearance 〈60 ml/min （renal insufficiency group; n=410） and those with estimated creatinine clearance ≥60 ml/min （control group; n=602）. Subgroup analysis was also made for patients with renal insufficiency between drug eluting stent （n=264） and bare metal stent implantation （n=146） during PCI. Results During follow-up （average 17 months） after successful PCI, all causes of death （7.1% vs 2.3%, P〈0.01） and cardiac death （3.4% vs 1.0%, all P〈0.01） were significantly higher in renal insufficiency group than in control group. For patients with moderate renal insufficiency, drug-eluting stent implantation reduced significantly all causes of death （5.3% vs 10.9%, P〈0.05） and occurrence of major cardiac adverse events （15.1% vs 24.6%, P〈0.05） compared with bare metal stents. Conclusions Moderate renal insufficiency is an important clinical factor influencing the mortality after PCI in patients with coronary artery disease and the use of drug-eluting stents should be the preferred therapy for the improvement of long-term outcomes in such patients.

关键词： long term outcome percutaneous coronary intervention renal insufficiency drug eluting stent