检索结果-南通市图书馆

Self-Assembly of Silver Clusters into One-and Two-Dimensional Structures and Highly Selective Methanol Sensing

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Research 2023年第1期2022卷 565-571页

作者： Zhaoxian Qin Zhiwen li Sachil sharma Yongwu Peng Rongchao Jin Gao li State Key laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Department of Chemistry Carnegie Mellon UniversityPittsburghPA 15213USA College of Materials Science and Engineering and College of Chemical Engineering Zhejiang University of TechnologyHangzhou 310014China University of Chinese Academy of Sciences 100049 BeijingChina

The development of new materials for the design of sensitive and responsive sensors has become a crucial research ***,two silver cluster-based polymers(Ag-CBPs),including one-dimensional[Ag_(22)(l1)_(8)(CF_(3)CO_(2))_(14)](CH_(3)OH)_(2))n chain and two-dimensional[Ag_(12)(l2)_(2)(CO_(2)CF_(3))_(14)(H_(2)O)_(4)(AgCO_(2)CF_(3))_(4)](HNEt_(3))_(2))_(n) film,are designed and used to simulate the human nose,an elegant sensor to smells,to distinguish organic *** study the relationship between the atomic structures of Ag-CBPs determined by x-ray diffraction and the electrical properties in the presence of organic solvents(e.g.,methanol and ethanol).The ligands,cations,and the ligated solvent molecules not only play an important role in the self-assembly process of Ag-CBP materials but also determine their physiochemical properties such as the sensing functionality.

关键词： silver Highly methanol

Involvement of adenosine and standardization of aqueous extract of ga.l.c(a.l.um sativum linn.)on cardioprotective and cardiodepressant properties in ischemic preconditioning and myocardial ischemia-reperfusion induced cardiac injury

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

The Journal of Biomedical Research 2012年第1期26卷 24-36页

作者： Ashish Kumar sharma Arshee Munajjam Bhawna Vaishnav Richa sharma Ashok sharma Kunal Kishore Akash sharma Divya sharma Rita Kumari Ashish Tiwari Santosh Kumar Singh Samir Gaur Vijay Singh Jatav Barthu Parthi Srinivasan Shyam Sunder Agarwal Department of Pharmacology Gyan Vihar School of PharmacySuresh Gyan Vihar University Department of Pharmacology Delhi Institute of Pharmaceutical Sciences & Research

The present study investigated the effect of ga.l.c （a.l.um sativum linn.） aqueous extracts on ischemic pre- conditioning and ischemia-reperfusion induced cardiac injury, as well as adenosine involvement in ischemic pre- conditioning and ga.l.c extract induced cardioprotection. A model of ischemia-reperfusion injury was esta.l.shed using langendorff apparatus. Aqueous extract of ga.l.c dose was standardized （0.5%, 0.4%, 0.3%, 0.2%, 0.1%, 0.07%, 0.05%, 0.03%, 0,01%）, and the 0.05% dose was found to be the most effective. Higher doses （more than 0.05%） were highly toxic, causing arrhythmia and cardiodepression, whereas the lower doses were ineffective. Ga.l.c exaggerated the cardioprotective effect of ischemic preconditioning. The cardioprotective effect of ischemic preconditioning and ga.l.c cardioprotection was significantly attenuated by theophylline （1,000 ~tmol/l） and 8-SPT （10 mg/kg, i.p.） and expressed by increased myocardial infarct size, increased lDH level, and reduced nitrite and adenosine levels. These findings suggest that adenosine is involved in the pharmacological and molecular mechanism of ga.l.c induced cardioprotection and mediated by the modulation of nitric oxide.

关键词： a.l.um sativum linn. ischemic preconditioning cardioprotection adenosine nitrite

Persistent free radicals in humin under redox conditions and their impact in transforming polycyclic aromatic hydrocarbons

在线全文

学校读者我要写书评

暂无评论

Frontiers of Environmental Science & Engineering 2020年第4期14卷 213-223页

作者： Hanzhong Jia Yafang Shi Xiaofeng Nie Song Zhao Tiecheng Wang Virender K.sharma College of Resources and Environment Northwest A&F UniversityYangling 712100China State Key laboratory of Soil Erosion and Dryland Farming on loess Plateau Institute of Soil and Water ConservationNorthwest A&F UniversityYangling 712100China Program for the Environment and Sustainability Department of Occupational and Environmental HealthSchool of Public HealthTexas A&M UniversityCollege StationTX 77843USA

The role of humic substance-associated persistent free radicals(PFRs)in the fate of organic contaminants under various redox conditions remains *** study examined the characterization of original metal-free peat humin(HM),and HM treated with varying concentrations of H2O2 and l-ascorbic acid(VC)(assigned as H2O2-HM and VC-HM).The concentration of PFRs in HM increased with the addition of VC/H2O2 at concentrations less than 0.08 mol/*** evolution of PFRs in HM under different environmental conditions(e.g.,oxic/anoxic and humidity)was *** types of PFRs were detected in HM:a relatively sta.l. radical existed in the original sample,and the other type,which was generated by redox treatments,wa s relatively *** spin densities of VC/H2O2-HM readily returned to the original value under relatively high humidity and oxic *** this process,the HM-associated"unsta.l."free radicals released an electron to O2,inducing the formation of reactive oxygen species(ROS,i.e.,·OH and·O2-).Th e generated ROS promoted the degradation of polycyclic aromatic hydrocarbons based on the radical quenching *** transformation rates followed the order naphthalene>phenanthrene>anthracene>benzo[a]*** results provide valua.l. insight into the HM-induced transformation of organic contaminants under natural conditions.

关键词： Humic substance Polycyclic aromatic hydrocarbons(PAHs) Persistent free radicals(PFRs) Redox Reactive oxygen species(ROS)

Control of peak pressures of an HCCI engine under varying swirl and operating parameters

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers in Energy 2016年第3期10卷 337-346页

作者： T. KARTHIKEYA sharma G. AMBA PRASAD RAO K. MADHU MURTHY Department of Mechanical Engineering NIT Warangal Warangal506004 India

The major advantages of homogeneous charge compression ignition （HCCI） are high efficiency in combination with low NOx-emissions. However, one of the major cha.l.nges with HCCI is the control of higher peak pressures which may damage the engine, limiting the HCCI engine life period. In this paper, an attempt is made to analyze computationa.l. the effect of induction swirl in controlling the peak pressures of an HCCI engine under various operating parameters. A single cylinder 1.6 l reentrant piston bowl diesel engine is chosen. For computational analysis, the ECFM-3Z model of STAR - CD is considered because it is suita.l. for analyzing the combustion processes in SI and CI engines. As an HCCI engine is a hybrid version of SI and CI engines, the ECFM- 3Z model with necessary modifications is used to analyze the peak pressures inside the combustion chamber. The ECFM-3Z model for HCCI mode of combustion is validated with the existing literature to make sure that the results obtained are accurate. Numerical experiments are performed to study the effect of varying properties like speed of the engine, piston bowl geometry, exhaust gas recirculation （EGR） and equivalence ratio under different swirl ratios in controlling the peak pressures inside the combustion chamber. The results show that the swirl ratio has a considera.l. impact on controlling the peak pressures of HCCI engine. A reduction in peak pressures are observed with a swirl ratio of 4 because of reduced in cylinder temperatures. The combined effect of four operating parameters, i.e., the speed of the engine, piston bowl geometry, EGR, and equivalence ratio with swirl ratios suggest that lower intake temperatures, reentrant piston bowl, higher engine speeds and higher swirl ratios are favora.l. in controlling the peak pressures.

关键词： HCCI engine ECFM-3Z Swirl ratio peak pressures engine speed piston bowl geometry

Biomaterials / bioinks and extrusion bioprinting

在线全文

学校读者我要写书评

暂无评论

Bioactive Materials 2023年第10期28卷 511-536页

作者： X.B.Chen A.Fazel Anvari-Yazdi X.Duan A.Zimmerling R.Gharraei N.K.sharma S.Sweilem l.Ning Department of Mechanical Engineering University of Saskatchewan57 Campus DrS7K 5A9SaskatoonCanada b Division of Biomedical EngineeringUniversity of Saskatchewan57 Campus DrSaskatoonS7K 5A9Canada c Department of Mechanical EngineeringCleveland State UniversityClevelandOH44115USA

Bioinks are formulations of biomaterials and living cells, sometimes with growth factors or other biomolecules, while extrusion bioprinting is an emerging technique to apply or deposit these bioinks or biomaterial solutions to create three-dimensional (3D) constructs with architectures and mechanical/biological properties that mimic those of native human tissue or organs. Printed constructs have found wide applications in tissue engineering for repairing or treating tissue/organ injuries, as well as in vitro tissue modelling for testing or validating newly developed therapeutics and vaccines prior to their use in humans. Successful printing of constructs and their subsequent applications rely on the properties of the formulated bioinks, including the rheological, mechanical, and biological properties, as well as the printing process. This article critica.l. reviews the latest developments in bioinks and biomaterial solutions for extrusion bioprinting, focusing on bioink synthesis and characterization, as well as the influence of bioink properties on the printing process. Key issues and cha.l.nges are also discussed along with recommendations for future research.

关键词： 3D bioprinting Extrusion Bioinks Biomaterials Tissue engineering

New Phenomenon of the Hysteresis of 4He in Vycor Glass

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics letters 1992年第2期9卷 83-85页

作者： JIN Xin XU Xiaonong YAN Yong a.l.Thomson D.F.Brewer S.Haynes N.sharma Department of Physics Nanjing UniversityNanjing 210008 Physics Building University of Sussex Brighton BN19QHEngland

The low t emperature part of hysteresis curves of the freezing and melting processes of ^(4)He in vycor glass with the lowest temperature O.4K were measured,as the pressure ranged from 36.45 to 55.18(1O^(5)Pa).Some novel characteristics of these curves were observed in such high temperature and pressure *** may result from the existence of superfluid ^(4)He.

关键词： freezing hysteresis curves

Drought-Tolerant Pseudomonas spp. Improve the Growth Performance of Finger Millet(Eleusine coracana.l.) Gaertn.)Under Non-Stressed and Drought-Stressed Conditions

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Pedosphere 2018年第2期28卷 227-240页

作者： Dinesh CHANDRA Rashmi SRIVASTAVA Bernard R.GlICK Anil K.sharma Department of Biological Science College of Basic Sciences and Humanities Govind Ballabh Pant University of Agriculture and Technology Department of Biology University of Waterloo

Application of plant growth-promoting bacteria(PGPB)is an environmenta.l. sustaina.l. option to reduce the effects of abiotic and biotic stresses on plant growth and *** 1-aminocyclopropane-1-carboxylic acid(ACC)deaminase-producing drought-tolerant bacteria were isolated from a rain-fed agriculture field in the Central Himalaya of Kumaun region,Uttarakhand,India and evaluated for their efficiency in improving finger millet(Eleusine coracana.l.)Gaertn.)plant growth under non-stressed and drought-stressed *** bacteria withstood a substrate metric potential of -1.0 MPa(30% polyethylene glycol 8000)and therefore were considered *** strains were identified as Pseudomonas *** fatty acid methyl ester analysis and 16S rRNA gene *** ACC deaminase activity of these strains was characterized at the biochemical level,and the presence of acd S gene,the structural gene for ACC deaminase,was confirmed by the polymerase chain *** sets of pot trials in glass house were set up,one for normal(non-stressed)and the other for drought-stressed *** 5 weeks,one set of plants was subjected to drought stress for 5 d,while the other set continued to be *** same growth parameters were recorded for both sets of plants after 40 d of plant *** results of pot trials showed that treatments inoculated with ACC deaminase-producing bacterial strains significantly improved the growth performance of finger millet plants and foliar nutrient content as compared to uninoculated treatments under both non-stressed and drought-stressed *** addition,a significant increase in antioxidant activity was observed,wherein bacterial stain inoculation improved plant fitness by protecting it from oxidative damage induced by drought.

关键词： antioxidant enzymes fatty acid methyl ester analysis plant growth-promoting bacteria polyethylene glycol polymerasechain reaction

Tillage, crop residue, and nutrient management effects *** organic carbon in rice-based cropping systems： A review

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Agriculture 2017年第1期16卷 1-15页

作者： Rajan Ghimire Sushil lamichhane Bharat sharma Acharya Prakriti Bista Upendra Man Sainju Agricultural Science Center New Mexico State University NM 88101 USA Soil Science Division Nepal Agricultural Research Council Khumaltar Nepal Department of Natural Resource Ecology and Management Oklahoma State University OK 74078 USA Columbia Basin Agricultural Research Center Oregon State University OR 97801 USA Northern Plains Agricultural Research lab USDA-ARS MT 59270 USA

Soil organic carbon （SOC） sequestration is one of the major agricultural strategies to mitigate greenhouse gas （GHG） emissions, enhance food security, and improve agricultural sustainability. This paper synthesizes the much-needed state- of-knowledge on the effects of tillage, crop residue, and nutrient management practices on SOC sequestration and identifies potential research gap, opportunities, and cha.l.nges in studying SOC dynamics in rice （Oryza sativa.l.）-based cropping systems in South Asia, mainly in Bangladesh, Bhutan, India, Nepal, Pakistan, and Sri lanka. Improved management prac- tices such as reduced- and no-tillage management, nitrogen （N） fertilizer and farmyard manure （FYM） application, and crop residue addition can improve SOC accumulation. Positive effects of no-tillage, crop residue addition, N addition through manure or compost application, and integration of organic and chemical fertilizers on SOC accumulation in rice-based cropping systems have been documented from South Asia. However, limited data and enormous discrepancies in SOC measurements across the region exist as the greatest cha.l.nge in increasing SOC sequestration and improving agricultural sustainability. More research on SOC as influenced by alternative tillage, crop residue, and nutrient management systems, and development of SOC monitoring system for existing long-term experiments will advance our understanding of the SOC dynamics in rice-based cropping systems and improve agricultural system sustainability in South Asia.

关键词： carbon mapping carbon sequestration crop residue no-tillage rice-wheat system

Ameliorative Role of Pre-Sowing Proline Treatment in Coriandrum sativum *** under Mercury Toxicity

在线全文

学校读者我要写书评

暂无评论

Phyton-International Journal of Experimental Botany 2021年第2期90卷 489-501页

作者： Dhriti Kapoor Kapani Kavani Amandeep Rattan Marco landi Anket sharma Department of Botany School of Bioengineering and BiosciencesLovely Professional UniversityPhagwara144411India Department of Botanical and Environmental Sciences Guru Nanak Dev UniversityAmritsar143005India Department of Agriculture Food and EnvironmentUniversity of PisaPisa56124Italy State Key laboratory of Subtropical Silviculture Zhejiang A&F UniversityHangzhou311300China

Heavy metal toxicity is one of the major ecosystem concerns globa.l. in present time and is also responsible for significant threat to agronomic *** current work was conducted to investigate the possible ameliorative role of proline in Coriandrum sativum *** treated with mercury(Hg).The seedlings were exposed to different concentrations of Hg(0,0.1,0.3 and 0.5 mM)for 20 *** effects of pre-sowing treatment with proline were studied on *** seedlings in terms of pigment(chlorophylls,carotenoids and anthocyanins),malondialdehyde(MDA),antioxidant compound(glutathione,total phenolic compounds,ascorbic acid)and osmolytes(proline,glycine betaine).Additiona.l.,activities of antioxidant enzymes,namely catalase(CAT),superoxide dismutase(SOD),ascorbate peroxidase(APX)and dehydroascorbate reductase(DHAR)were also studied.A strong decline of photosynthetic pigment concentrations was observed in leaves of *** under Hg *** of seeds with proline reduced the loss of photosynthetic pigments,counteract Hg-triggered oxidative stress,likely preserving the functionality of antioxidant apparatus under Hg *** increment of total polyphenols and glycine betaine also contributed in ameliorating Hg toxicity,suggesting the use of exogenous proline as a potential method to enhance the plant tolerance against heavy metal stress.

关键词： Anthocyanins Hg stress metal toxicity polyphenols proline pre-treatment