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Sythesis, Characterization and Catalysis of [ η~5,η~1-C_5H_4-CHPh-PhO]TiCl_2
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作者 WANG Jian hui, MU Ying ** , PU Wei ming ZHANG Yue tao, YANG Guang di and LIU Ju zheng (Department of Chemistry, Jilin University, Changchun 130023, P.R. China) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2001年第1期115-116,共2页
关键词 Metallocene Catalyst CYCLOPEnTADIEnYL GROUP 分类号:O6 文献标识码:A 文章编号:1005-9040(2001)-01-115-02 In recent years constrained-geometry GROUP 4 METALLOCEnE catalysts HAVE received considerable attention due to their importance in commercial . The structural feature of this type of METALLOCEnES is that one of the two CYCLOPEnTADIEnYL groups in ansa-metallocene complexes is replaced by a heteroatom such as nitrogen phosphorus[2] or oxygen[3] and etc. In comparison with biscyclopentadienyl metallocenes the constrained-geometry METALLOCEnE catalysts HAVE more open space for olefin coordination which allows larger α-olefins to copolymerize with ethylene easily. This kind of compounds would HAVE a better catalytic performance if a PHEnOL GROUP were introduced into the ligand framework since the O in the PHEnOL GROUP is more negative than n P in the amido- or phosphido- groups and the whole molecule with the phenol-cyclopentadienyl ligand will be more stable compared to the complexes with amido- or……
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Gunn器件中畴的静止-渡越-静止模式的实验观察和计算机模拟
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作者 王守武 郑一阳 +1 位作者 郗小林 张进昌 《Journal of Semiconductors》 EI CAS 1983年第4期321-333,共13页
本文讨论在GaAs n^+-n-n^+夹层结构的Cunn器件中畴的静止-渡越-静止模式,进行了实验观察和计算机模拟,指出在超过阈值的偏置电压下,当畴的耗尽层进入阳极附近的高掺杂区后,会逐渐停止下来形成准静态畴,这时畴外电场达到最大值.如果这时... 本文讨论在GaAs n^+-n-n^+夹层结构的Cunn器件中畴的静止-渡越-静止模式,进行了实验观察和计算机模拟,指出在超过阈值的偏置电压下,当畴的耗尽层进入阳极附近的高掺杂区后,会逐渐停止下来形成准静态畴,这时畴外电场达到最大值.如果这时阴极凹口仍不能形成新畴,则准静态畴将进一步调整成为真正的静止畴,而畴外电场也将由最大值下降到一个与偏压无关的固定值.经过理论分析,得到了静止畴所固有的与外加偏压无关的畴外电场与有源区掺杂浓度的关系式,并和计算机模拟的结果相比较,得到很好的符合.如果偏压的增加使准静态畴所对应的畴外电场最大值已经足够使阴极凹口形成新的畴,则静止畴将转变为渡越畴.如果偏压继续增加,使积累层尾部覆盖了阴极凹口,则畴会再次静止下来,直到偏压增加到畴发生雪崩为止.计算和实验表明,后一个静止区的电压变化范围要比前一个大得多.本文还讨论了两个转变电压和温度的关系及扩散系数对静止畴的影响. 展开更多
关键词 The TRAnSFORMATIOnS between stationary and TRAnSIT DOMAInS in a GUnn device which has n^+-n-n^+ SAnDWICH structure with doping gradient near the anode are investigated.Experimental observation computer simulation carried out.When th
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Model of Universe as Described by Dynamic Universe Model
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作者 Satyavarapu Naga Parameswara Gupta 《Open Journal of Modelling and Simulation》 2019年第1期41-78,共38页
In this paper we will see the model of Universe according to Dynamic Universe Model of Cosmology by visualizing various processes that are happening in the Universe as per experimental evidences. For simplifying the m... In this paper we will see the model of Universe according to Dynamic Universe Model of Cosmology by visualizing various processes that are happening in the Universe as per experimental evidences. For simplifying the matter here, we will see in part 1: about the Galaxy life cycle, where the birth and death of Galaxies discussed. Probably Universe gives guidance for the movement of Galaxies. We call this Part 1: Thinking and Reproducing Universe or Mindless Universe? (Galaxy life cycle). We see every day Sun, Stars, Galaxies etc., dissipating enormous energy in the form of radiation by the way of fusion of Hydrogen to helium. So after sometime all the Hydrogen is spent and Universe will die, is it not? … Dynamic Universe Model says that the energy in the form of electromagnetic radiation passing grazingly near any gravitating mass changes in frequency and finally will convert into neutrinos (mass). Hence Dynamic Universe Model proposes another process where energy will be converted back into matter and the cycle energy to mass to energy continues, sustaining the Universe to maintain this present status for ever in this form something like a Steady state model without any expansion. This we will see in Part 2: Energy - Mass - Energy Cycle. After converting energy into mass “how various elements are formed and where they are formed?” will be next logical question. Dynamic Universe Model says that these various particles change into higher massive particles or may get bombarded into stars or planets and various elements are formed. Here we bifurcate the formation of elements into 6 processes. They are for Elementary particles and elements generated in frequency changing process, By Cosmic rays, By Small stars, By Large Stars, By Super Novae and Manmade elements By Neutron Stars. This we will discuss in Part 3: Nucleosynthesis. 展开更多
关键词 DYnAMIC UnIVERSE MODEL Hubble Space Telescope (HST) SITA Simulations (SITA-Simulation of Inter Intra Tautness Attraction Forces Used by DYnAMIC UnIVERSE Model) Singularity-Free COSMOLOGY Blue Shifted GALAXIES Red Shifted GALAXIES Grazing Radiation Frequency Changes Formation of Elements nUCLEOSYnTHESIS DYnAMIC UnIVERSE MODEL Energy to Mass Conversion Methods: n-Body Simulations-Gravitation-Cosmology
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GLYX-13 pretreatment ameliorates long-term isoflurane exposure-induced cognitive impairment in mice 被引量:4
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作者 Huan Liu Xiang-Dan Gong +3 位作者 Xin Zhao Yue Qian Xiao-Ping Gu Tian-Jiao Xia 《Neural Regeneration Research》 SCIE CAS CSCD 2020年第1期128-135,共8页
Accumulating evidence indicates that inhalation anesthetics induce or increase the risk of cognitive impairment.GLYX-13(rapastinel)acts on the glycine site of N-methyl-D-aspartate receptors(NMDARs)and has been shown t... Accumulating evidence indicates that inhalation anesthetics induce or increase the risk of cognitive impairment.GLYX-13(rapastinel)acts on the glycine site of N-methyl-D-aspartate receptors(NMDARs)and has been shown to enhance hippocampus-dependent learning and memory function.However,the mechanisms by which GLYX-13 affects learning and memory function are still unclear.In this study,we investigated these mechanisms in a mouse model of long-term anesthesia exposure.Mice were intravenously administered 1 mg/kg GLYX-13 at 2 hours before isoflurane exposure(1.5%for 6 hours).Cognitive function was assessed using the contextual fear conditioning test and the novel object recognition test.The mRNA expression and phosphorylated protein levels of NMDAR pathway components,N-methyl-D-aspartate receptor subunit 2B(NR2B)-Ca^2+/calmodulin dependent protein kinaseⅡ(CaMKII)-cyclic adenosine monophosphate response element binding protein(CREB),in the hippocampus were evaluated by quantitative RT-PCR and western blot assay.Pretreatment with GLYX-13 ameliorated isoflurane exposure-induced cognitive impairment and restored NR2B,CaMKII and CREB mRNA and phosphorylated protein levels.Intracerebroventricular injection of KN93,a selective CaMKII inhibitor,significantly diminished the effect of GLYX-13 on cognitive function and NR2B,CaMKII and CREB levels in the hippocampus.Taken together,our findings suggest that GLYX-13 pretreatment alleviates isoflurane-induced cognitive dysfunction by protecting against perturbation of the NR2B/CaMKII/CREB signaling pathway in the hippocampus.Therefore,GLYX-13 may have therapeutic potential for the treatment of anesthesia-induced cognitive dysfunction.This study was approved by the Experimental Animal Ethics Committee of Drum Tower Hospital affiliated to the Medical College of Nanjing University,China(approval No.20171102)on November 20,2017. 展开更多
关键词 Ca^2+/calmodulin-dependent PROTEIn kinaseⅡ cognitive impairment contextual FEAR conditioning cyclic adenosine MOnOPHOSPHATE response element binding PROTEIn GLYX-13 ISOFLURAnE n-METHYL-D-ASPARTATE receptor novel object recognition rapastinel
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Dietary Green Tea Extract and Antioxidants Improve Insulin Secretory Functions of Pancreatic β-Cells in Mild and Severe Experimental Rodent Model of Chronic Pancreatitis
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作者 Galande Sheethal Ranjeet K. Tokala +7 位作者 Pavan Pondugala Krishna Vemula Vijayalakshmi Venkatesan Pothani Suresh Surya Satyanarayana Singh Guduru Venkat Rao Duvvur Nageshwar Reddy Mitnala Sasikala 《Open Journal of Endocrine and Metabolic Diseases》 2024年第2期53-72,共20页
Chronic pancreatitis (CP) is a progressive inflammatory disorder of the pancreas. It is predominantly idiopathic (with an unknown cause) in India and mostly due to alcohol in the West. Diabetes that occur secondary to... Chronic pancreatitis (CP) is a progressive inflammatory disorder of the pancreas. It is predominantly idiopathic (with an unknown cause) in India and mostly due to alcohol in the West. Diabetes that occur secondary to chronic pancreatitis (T3c Diabetes) is often brittle, and is difficult to attain normoglycemia with conventional treatment requiring multiple doses of insulin. Mild and severe model of CP was induced in mice by repeated intraperitoneal injections of cerulein and L-arginine respectively with an intent to study islet dysfunction and develop therapeutic strategy in animal models of CP. Dietary intervention of epigallocatechin-3-gallate (EGCG) was tested in both the models of CP for its beneficial effects on insulin secretory functions. Pancreata collected upon euthanasia were used to study alterations in the morphology of pancreatic parenchyma and inflammation by staining with H&E and fibrotic changes by Masson’s trichrome and picrosirius staining. Insulin secretory functions of islets were evaluated to test the efficacy of the dietary intervention on β-cell functions. Intraperitoneal glucose tolerance test was performed to monitor the glucose homeostasis before and after the dietary intervention. Both the models resulted in CP with dispersed acini, inflammation and fibrosis. The loss of acini and extent of fibrosis was more in L-arginine model. 2-fold improvement in glucose-stimulated insulin secretory functions of islets was observed with 0.5% EGCG dietary intervention in cerulein model of CP and 1.6-fold in L-arginine model of CP. A further improvement in insulin secretion by 3.2-fold was observed with additional dietary supplements like N-acetyl cysteine, curcumin in combination with EGCG. Our results thus demonstrate and highlight the therapeutic potential of dietary green tea (EGCG) supplementation in reversing islet dysfunction and improving glucose homeostasis in experimental chronic pancreatitis in mice. 展开更多
关键词 Dietary Intervention C57BL6/J Mice Epigallocatechin-3-Gallate n-Acetyl Cysteine Curcumin Chronic Pancreatitis ISLETS Glucose Stimulated Insulin Secretion
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(n,d)-(Ext)-phantom态射与(n,d)-环
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作者 余君丽 张春霞 《中山大学学报(自然科学版)(中英文)》 CAS CSCD 北大核心 2024年第1期154-165,共12页
引入了(n,d)-phantom态射与(n,d)-Ext-phantom态射的概念.利用它们,给出了(n,d)-环、n-遗传环以及n-正则环的一系列新刻画.
关键词 (n d)-phantom态射 (n d)-Ext-phantom态射 n-凝聚环 (n d)-环 n-遗传环
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A Comparative Analysis of the New -3(-n) - 1 Remer Conjecture and a Proof of the 3n + 1 Collatz Conjecture
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作者 Mike Remer 《Journal of Applied Mathematics and Physics》 2023年第8期2216-2220,共5页
This scientific paper is a comparative analysis of two mathematical conjectures. The newly proposed -3(-n) - 1 Remer conjecture and how it is related to and a proof of the more well known 3n + 1 Collatz conjecture. An... This scientific paper is a comparative analysis of two mathematical conjectures. The newly proposed -3(-n) - 1 Remer conjecture and how it is related to and a proof of the more well known 3n + 1 Collatz conjecture. An overview of both conjectures and their respective iterative processes will be presented. Showcasing their unique properties and behavior to each other. Through a detailed comparison, we highlight the similarities and differences between these two conjectures and discuss their significance in the field of mathematics. And how they prove each other to be true. 展开更多
关键词 -3(-n) - 1 Remer Conjecture 3n + 1 Collatz Conjecture Comparative Analysis PROOF natural numbers Integer Sequences Factorial Processes Par-tial Differential Equations Bounded Values Collatz Conjecture Collatz Algo-rithm Collatz Operator Collatz Compliance And Mathematical Conjectures
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Grain yield and N uptake of maize in response to increased plant density under reduced water and nitrogen supply conditions
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作者 Jingui Wei Qiang Chai +5 位作者 Wen Yin Hong Fan Yao Guo Falong Hu Zhilong Fan QimingWang 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期122-140,共19页
The development of modern agriculture requires the reduction of water and chemical N fertilizer inputs.Increasing the planting density can maintain higher yields,but also consumes more of these restrictive resources.H... The development of modern agriculture requires the reduction of water and chemical N fertilizer inputs.Increasing the planting density can maintain higher yields,but also consumes more of these restrictive resources.However,whether an increased maize density can compensate for the negative effects of reduced water and N supply on grain yield and N uptake in the arid irrigated areas remains unknown.This study is part of a long-term positioning trial that started in 2016.A split-split plot field experiment of maize was implemented in the arid irrigated area of northwestern China in 2020 to 2021.The treatments included two irrigation levels:local conventional irrigation reduced by 20%(W1,3,240 m^(3)ha^(-1))and local conventional irrigation(W2,4,050 m^(3)ha^(-1));two N application rates:local conventional N reduced by 25%(N1,270 kg ha^(-1))and local conventional N(360 kg ha^(-1));and three planting densities:local conventional density(D1,75,000 plants ha^(-1)),density increased by 30%(D2,97,500 plants ha-1),and density increased by 60%(D3,120,000 plants ha^(-1)).Our results showed that the grain yield and aboveground N accumulation of maize were lower under the reduced water and N inputs,but increasing the maize density by 30% can compensate for the reductions of grain yield and aboveground N accumulation caused by the reduced water and N supply.When water was reduced while the N application rate remained unchanged,increasing the planting density by 30% enhanced grain yield by 13.9% and aboveground N accumulation by 15.3%.Under reduced water and N inputs,increasing the maize density by 30% enhanced N uptake efficiency and N partial factor productivity,and it also compensated for the N harvest index and N metabolic related enzyme activities.Compared with W2N2D1,the N uptake efficiency and N partial factor productivity increased by 28.6 and 17.6%under W1N1D2.W1N2D2 had 8.4% higher N uptake efficiency and 13.9% higher N partial factor productivity than W2N2D1.W1N2D2 improved urease activity and nitrate reductase activity by 5.4% at the R2(blister)stage and 19.6% at the V6(6th leaf)stage,and increased net income and the benefit:cost ratio by 22.1 and 16.7%,respectively.W1N1D2 and W1N2D2 reduced the nitrate nitrogen and ammoniacal nitrogen contents at the R6 stage in the 40-100 cm soil layer,compared with W2N2D1.In summary,increasing the planting density by 30% can compensate for the loss of grain yield and aboveground N accumulation under reduced water and N inputs.Meanwhile,increasing the maize density by 30% improved grain yield and aboveground N accumulation when water was reduced by 20% while the N application rate remained constant in arid irrigation areas. 展开更多
关键词 water and n reduction plant density MAIZE grain yield n uptake compensation effect
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Boosting Fischer-Tropsch Synthesis via Tuning of N Dopants in TiO_(2)@CN-Supported Ru Catalysts
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作者 Xincheng Li Yunhao Liu +10 位作者 Dejian Zhao Shuaishuai Lyu Jingwei Ye Xiaoshen Li Peipei Wu Ye Tian Yingtian Zhang Tong Ding Song Song Qingpeng Cheng Xingang Li 《Transactions of Tianjin University》 EI CAS 2024年第1期90-102,共13页
Nitrogen(N)-doped carbon materials as metal catalyst supports have attracted signifi cant attention,but the eff ect of N dopants on catalytic performance remains unclear,especially for complex reaction processes such ... Nitrogen(N)-doped carbon materials as metal catalyst supports have attracted signifi cant attention,but the eff ect of N dopants on catalytic performance remains unclear,especially for complex reaction processes such as Fischer-Tropsch synthesis(FTS).Herein,we engineered ruthenium(Ru)FTS catalysts supported on N-doped carbon overlayers on TiO_(2)nanoparticles.By regulating the carbonization temperatures,we successfully controlled the types and contents of N dopants to identify their impacts on metal-support interactions(MSI).Our fi ndings revealed that N dopants establish a favorable surface environment for electron transfer from the support to the Ru species.Moreover,pyridinic N demonstrates the highest electron-donating ability,followed by pyrrolic N and graphitic N.In addition to realizing excellent catalytic stability,strengthening the interaction between Ru sites and N dopants increases the Ru^(0)/Ru^(δ+)ratios to enlarge the active site numbers and surface electron density of Ru species to enhance the strength of adsorbed CO.Consequently,it improves the catalyst’s overall performance,encompassing intrinsic and apparent activities,as well as its ability for carbon chain growth.Accordingly,the as-synthesized Ru/TiO_(2)@CN-700 catalyst with abundant pyridine N dopants exhibits a superhigh C_(5+)time yield of 219.4 mol CO/(mol Ru·h)and C_(5+)selectivity of 85.5%. 展开更多
关键词 Fischer-Tropsch synthesis n-doped carbon materials Ruthenium catalyst Pyridinic n Metal-n interaction
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Enhancing Green Ammonia Electrosynthesis Through Tuning Sn Vacancies in Sn‑Based MXene/ MAX Hybrids
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作者 Xinyu Dai Zhen‑Yi Du +10 位作者 Ying Sun Ping Chen Xiaoguang Duan Junjun Zhang Hui Li Yang Fu Baohua Jia Lei Zhang Wenhui Fang Jieshan Qiu Tianyi Ma 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第5期154-168,共15页
Renewable energy driven N_(2) electroreduction with air as nitrogen source holds great promise for realizing scalable green ammonia production.However,relevant out-lab research is still in its infancy.Herein,a novel S... Renewable energy driven N_(2) electroreduction with air as nitrogen source holds great promise for realizing scalable green ammonia production.However,relevant out-lab research is still in its infancy.Herein,a novel Sn-based MXene/MAX hybrid with abundant Sn vacancies,Sn@Ti_(2)CTX/Ti_(2)SnC–V,was synthesized by controlled etching Sn@Ti_(2)SnC MAX phase and demonstrated as an efficient electrocatalyst for electrocatalytic N2 reduction.Due to the synergistic effect of MXene/MAX heterostructure,the existence of Sn vacancies and the highly dispersed Sn active sites,the obtained Sn@Ti2CTX/Ti_(2)SnC–V exhibits an optimal NH_(3) yield of 28.4μg h^(−1) mg_(cat)^(−1) with an excellent FE of 15.57% at−0.4 V versus reversible hydrogen electrode in 0.1 M Na_(2)SO_(4),as well as an ultra-long durability.Noticeably,this catalyst represents a satisfactory NH3 yield rate of 10.53μg h^(−1) mg^(−1) in the home-made simulation device,where commercial electrochemical photovoltaic cell was employed as power source,air and ultrapure water as feed stock.The as-proposed strategy represents great potential toward ammonia production in terms of financial cost according to the systematic technical economic analysis.This work is of significance for large-scale green ammonia production. 展开更多
关键词 Green ammonia synthesis n2 electroreduction Renewable energy Sn MXene/MAX hybrid
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Clinical outcome and prognostic factors of T4N0M0 colon cancer after R0 resection:A retrospective study
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作者 Bang Liu Zhao-Xiong Zhang +3 位作者 Xin-Yang Nie Wei-Lin Sun Yong-Jia Yan Wei-Hua Fu 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第5期1869-1877,共9页
BACKGROUND Paradoxically,patients with T4N0M0(stage II,no lymph node metastasis)colon cancer have a worse prognosis than those with T2N1-2M0(stage III).However,no previous report has addressed this issue.AIM To screen... BACKGROUND Paradoxically,patients with T4N0M0(stage II,no lymph node metastasis)colon cancer have a worse prognosis than those with T2N1-2M0(stage III).However,no previous report has addressed this issue.AIM To screen prognostic risk factors for T4N0M0 colon cancer and construct a prognostic nomogram model for these patients.METHODS Two hundred patients with T4N0M0 colon cancer were treated at Tianjin Medical University General Hospital between January 2017 and December 2021,of which 112 patients were assigned to the training cohort,and the remaining 88 patients were assigned to the validation cohort.Differences between the training and validation groups were analyzed.The training cohort was subjected to multi-variate analysis to select prognostic risk factors for T4N0M0 colon cancer,followed by the construction of a nomogram model.RESULTS The 3-year overall survival(OS)rates were 86.2%and 74.4%for the training and validation cohorts,respectively.Enterostomy(P=0.000),T stage(P=0.001),right hemicolon(P=0.025),irregular review(P=0.040),and carbohydrate antigen 199(CA199)(P=0.011)were independent risk factors of OS in patients with T4N0M0 colon cancer.A nomogram model with good concordance and accuracy was constructed.CONCLUSION Enterostomy,T stage,right hemicolon,irregular review,and CA199 were independent risk factors for OS in patients with T4N0M0 colon cancer.The nomogram model exhibited good agreement and accuracy. 展开更多
关键词 T4n0M0 colon cancer PROGnOSIS Multivariate analysis nOMOGRAM Colon cancer
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Impact on Soil Organic C and Total Soil N from Cool- and Warm-Season Legumes Used in a Green Manure-Forage Cropping System
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作者 Clark B. Neely Francis M. Rouquette Jr. +3 位作者 Cristine L.S. Morgan Frank M. Hons William L. Rooney Gerald R. Smith 《Agricultural Sciences》 2024年第3期333-357,共25页
Annual forage legumes are important components of livestock production systems in East Texas and the southeastern US. Forage legumes contribute nitrogen (N) to cropping systems through biological N fixation, and their... Annual forage legumes are important components of livestock production systems in East Texas and the southeastern US. Forage legumes contribute nitrogen (N) to cropping systems through biological N fixation, and their seasonal biomass production can be managed to complement forage grasses. Our research objectives were to evaluate both warm- and cool-season annual forage legumes as green manure for biomass, N content, ability to enhance soil organic carbon (SOC) and soil N, and impact on post season forage grass crops. Nine warm-season forage legumes (WSL) were spring planted and incorporated as green manure in the fall. Forage rye (Secale cereale L.) was planted following the incorporation of WSL treatments. Eight cool-season forage legumes (CSL) were fall planted in previously fallow plots and incorporated as green manure in late spring. Sorghum-sudangrass (Sorghum bicolor x Sorghum bicolor var. sudanense) was planted over all treatments in early summer after forage rye harvest and incorporation of CSL treatments. Sorghum-sudangrass was harvested in June, August and September, and treatments were evaluated for dry matter and N concentration. Soil cores were taken from each plot, split into depths of 0 to 15, 15 to 30 and 30 to 60 cm, and soil C and N were measured using combustion analysis. Nylon mesh bags containing plant samples were buried at 15 cm and used to evaluate decomposition rate of above ground legume biomass, including change in C and N concentrations. Mungbean (Vigna radiata L. [Wilczek]) had the highest shoot biomass yield (6.24 t DM ha<sup>-1</sup>) and contributed the most total N (167 kg∙ha<sup>-1</sup>) and total C (3043 kg∙ha<sup>-1</sup>) of the WSL tested. Decomposition rate of WSL biomass was rapid in the first 10 weeks and very slow afterward. Winter pea (Pisum sativum L. spp. sativum), arrow leaf clover (Trifolium vesiculosum Savi.), and crimson clover (Trifolium incarnatum L.) were the most productive CSL in this trial. Austrian winter pea produced 8.41 t DM ha<sup>-1</sup> with a total N yield of 319 kg N ha<sup>-1</sup> and total C production of 3835 kg C ha<sup>-1</sup>. The WSL treatments had only small effects on rye forage yield and N concentration, possibly due to mineralization of N from a large SOC pool already in place. The CSL treatments also had only minimal effects on sorghum-sudangrass forage production. Winter pea, arrow leaf and crimson clover were productive cool season legumes and could be useful as green manure crops. Mungbean and cowpea (Vigna unguiculata [L.] Walp.) were highly productive warm season legumes but may include more production risk in green manure systems due to soil moisture competition. 展开更多
关键词 Annual Legumes Soil n Soil Organic C Green Manure Deer Browse Forage Cropping Systems
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Hydrologic Response to Future Climate Change in the Dulong-Irra-waddy River Basin Based on Coupled Model Intercomparison Project 6
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作者 XU Ziyue MA Kai +1 位作者 YUAN Xu HE Daming 《Chinese Geographical Science》 SCIE CSCD 2024年第2期294-310,共17页
Within the context of the Belt and Road Initiative(BRI)and the China-Myanmar Economic Corridor(CMEC),the Dulong-Ir-rawaddy(Ayeyarwady)River,an international river among China,India and Myanmar,plays a significant role... Within the context of the Belt and Road Initiative(BRI)and the China-Myanmar Economic Corridor(CMEC),the Dulong-Ir-rawaddy(Ayeyarwady)River,an international river among China,India and Myanmar,plays a significant role as both a valuable hydro-power resource and an essential ecological passageway.However,the water resources and security exhibit a high degree of vulnerabil-ity to climate change impacts.This research evaluates climate impacts on the hydrology of the Dulong-Irrawaddy River Basin(DIRB)by using a physical-based hydrologic model.We crafted future climate scenarios using the three latest global climate models(GCMs)from Coupled Model Intercomparison Project 6(CMIP6)under two shared socioeconomic pathways(SSP2-4.5 and SSP5-8.5)for the near(2025-2049),mid(2050-2074),and far future(2075-2099).The regional model using MIKE SHE based on historical hydrologic processes was developed to further project future streamflow,demonstrating reliable performance in streamflow simulations with a val-idation Nash-Sutcliffe Efficiency(NSE)of 0.72.Results showed that climate change projections showed increases in the annual precip-itation and potential evapotranspiration(PET),with precipitation increasing by 11.3%and 26.1%,and PET increasing by 3.2%and 4.9%,respectively,by the end of the century under SSP2-4.5 and SSP5-8.5.These changes are projected to result in increased annual streamflow at all stations,notably at the basin’s outlet(Pyay station)compared to the baseline period(with an increase of 16.1%and 37.0%at the end of the 21st century under SSP2-4.5 and SSP5-8.5,respectively).Seasonal analysis for Pyay station forecasts an in-crease in dry-season streamflow by 31.3%-48.9%and 22.5%-76.3%under SSP2-4.5 and SSP5-8.5,respectively,and an increase in wet-season streamflow by 5.8%-12.6%and 2.8%-33.3%,respectively.Moreover,the magnitude and frequency of flood events are pre-dicted to escalate,potentially impacting hydropower production and food security significantly.This research outlines the hydrological response to future climate change during the 21st century and offers a scientific basis for the water resource management strategies by decision-makers. 展开更多
关键词 climate change hydrologic response Coupled Model Intercomparison Project 6(CMIP6) MIKE SHE(Système Hydrologique Europeén) Dulong-Irrawaddy River Basin
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Optical properties for N,N’-bis (lnaphyhly)N,N’-diphenyl-1,1’-biphenyl-4,4’-diamine and tris (8-hydroxyquinolinato) aluminum in organic light emitting devices 被引量:1
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作者 Mei Yee Lim Wan Mahmood Mat Yunus +1 位作者 Zainal Abidin Talib Anuar Kassim 《Natural Science》 2010年第6期631-634,共4页
The optical properties of N,N’-bis (Inaphthyl)N,N’-diphenyl-1,1’-biphenyl-4,4’-diamine (NPB) and tris (8-hydroxyquinolinato) aluminum (Alq3) organic materials used as hole transport and electron transport layers i... The optical properties of N,N’-bis (Inaphthyl)N,N’-diphenyl-1,1’-biphenyl-4,4’-diamine (NPB) and tris (8-hydroxyquinolinato) aluminum (Alq3) organic materials used as hole transport and electron transport layers in organic light-emitting devices (OLED) have been investigated. The NPB and Alq3 layers were prepared using thermal evaporation method. The results show that the energy band gap of Alq3 is thickness independence while the energy band gap of NPB decreases with the increasing of sample thickness. For the case of photoluminescence the Alq3 with thickness of 84 nm shows the highest relative intensity peak at 510 nm. 展开更多
关键词 Energy Band Gap n n’-Bis (Inaphthyl) -n n’-Diphenyl-1 1’-Biphenyl-4 4’-Diamine Tris (8 Hydroxyquinolinato) Aluminum Organic Light Emitting Diode Photoluminescence
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Effects of Coagulation and Ozonation Pretreatments on Biochemical Treatment of Fluid Catalytic Cracking Wastewater
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作者 Ibrah Landi Ali Lu Jun 《Journal of Environmental Protection》 2024年第2期156-172,共17页
Fluid catalytic cracking (FCC) salty wastewaters, containing quaternary ammonium compounds (QACs), are very difficult to treat by biochemical process. Anoxic/oxic (A/O) biochemical system, based on nitrification and d... Fluid catalytic cracking (FCC) salty wastewaters, containing quaternary ammonium compounds (QACs), are very difficult to treat by biochemical process. Anoxic/oxic (A/O) biochemical system, based on nitrification and denitrification reactions, was used to assess their possible biodegradation. Because of the negative effects of high salt concentration (3%), heavy metals and toxic organic matter on microorganisms’ activities, some techniques consisting of dilution, coagulation and flocculation, and ozonation pretreatments, were gradually tested to evaluate chemical oxygen demand (COD), ammonia-nitrogen (ammonia-N) and total nitrogen (TN) removal rates. In this process of FCC wastewater, starting with university-domesticated sludge, the ammonia-N and TN removal rates were worst. However, when using domesticated SBR’s sludge and operating with five-fold daily diluted influent (thus reducing salt concentration), the ammonia-N removal reached about 57% while the TN removal rate was less than 37% meaning an amelioration of the nitrification process. However, by reducing the dilution factors, these results were inflected after some days of operation, with ammonia-N removal decreasing and TN barely removed meaning a poor nitrification. Even by reducing heavy metals concentration with coagulation/flocculation process, the results never changed. Thereafter, by using ozonation pre-treatment to degrade the detected organic matter of di-tert-butylphenol and certain isoparaffins, COD, ammonia-N and TN removal rates reached 92%, 62% and 61%, respectively. These results showed that the activities of the microorganisms were increased, thus indicating a net denitrification and nitrification reactions improvement. 展开更多
关键词 Ammonia-n Anoxic and Oxic (A/O) Reactor Coagulation and Sedimentation FCC Wastewater Ozone Total nitrogen (Tn)
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Pattern of disharmony between the heart and kidney: Theoretical basis, identification and treatment
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作者 Jian Dong Tianfang Wang +1 位作者 Lihong Zhao Xinran Chen 《Journal of Traditional Chinese Medical Sciences》 2017年第4期317-321,共5页
'Harmony between the heart and kidney' refers to the physiological relationship between these two zang organs in Chinese medicine,while 'disharmony between the heart and kidney' (also called disharmony... 'Harmony between the heart and kidney' refers to the physiological relationship between these two zang organs in Chinese medicine,while 'disharmony between the heart and kidney' (also called disharmony between fire and water) refers to the pathological state.The pattern of disharmony between the heart and kidney is widely observed in patients with insomnia,anxiety disorder and menopausal syndrome,etc..In order to gain a full and systematical understanding of this pattern,from the perspective of ancient Chinese philosophy and zang-fu theory in Chinese medicine,we systematically reviewed and discussed the functions and physiological characteristics of the heart and kidney,the origin and development of theories relating to heart-kidney relationship,the pathogenesis and identification of the pattern,as well as the commonly used classical formulas for its treatment,including Coptis and DonkeyHide Gelatin Decoction (Huánglián (E)jiāo Tāng) and Grand Communication Pill (Jiāotài Wán).Two examples of clinical modifications of these formulas in the treatment of insomnia and menopausal syndrome are provided in this article.It should be noted that in clinical practice,these formulas should be used flexibly,and modified in accordance to the condition of the patient. 展开更多
关键词 Harmony BETWEEn the HEART and KIDnEY Disharmony BETWEEn the HEART and KIDnEY PATTERn of disharmony BETWEEn the HEART and KIDnEY Coptis and Donkey-Hide Gelatin Decoction (Huánglián (E)jiāo ng) Grand Communication Pill (Jiāotài n)
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(G,N)蕴涵满足U-MP、U-MT、U-HS不等式的条件
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作者 于鹏 党思昱 李冉冉 《陕西科技大学学报》 北大核心 2024年第2期224-232,共9页
(G,N)-蕴涵是由不一定结合的二元分组函数G与模糊否定N生成的一类重要模糊蕴涵算子,深入研究(G,N)-蕴涵算子所满足的性质,对于推广(G,N)-蕴涵在模糊推理中的应用具有积极意义.本文针对(G,N)-蕴涵是否满足U-Modus Ponens,U-Modus Tollens... (G,N)-蕴涵是由不一定结合的二元分组函数G与模糊否定N生成的一类重要模糊蕴涵算子,深入研究(G,N)-蕴涵算子所满足的性质,对于推广(G,N)-蕴涵在模糊推理中的应用具有积极意义.本文针对(G,N)-蕴涵是否满足U-Modus Ponens,U-Modus Tollens与U-Hypothetical Syllogism不等式的问题展开讨论,给出了(G,N)-蕴涵在一致模U取幂等一致模,可表示一致模情形下,(G,N)-蕴涵满足上述不等式的条件. 展开更多
关键词 一致模 (G n)-蕴涵 U-Modus Ponens推理规则 U-Modus Tollens推理规则
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信使RNA甲基化在肾脏病中研究进展
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作者 张诗文 栾军军 周华 《临床肾脏病杂志》 2024年第2期143-150,共8页
信使RNA(messenger RNA,mRNA)甲基化修饰近年来研究普遍,包括N6-甲基腺苷(m^(6)A)、N5-甲基胞苷(m^(5)C)和N1-甲基腺苷(m^(1)A)等多种修饰在内。mRNA甲基化修饰的动态可逆生物学过程包括“编码器(Writer)”“消码器(Eraser)”和“读码器... 信使RNA(messenger RNA,mRNA)甲基化修饰近年来研究普遍,包括N6-甲基腺苷(m^(6)A)、N5-甲基胞苷(m^(5)C)和N1-甲基腺苷(m^(1)A)等多种修饰在内。mRNA甲基化修饰的动态可逆生物学过程包括“编码器(Writer)”“消码器(Eraser)”和“读码器(Reader)”的参与,甲基化修饰中出现异常,可导致多种疾病的发生、发展,其中包括急性肾损伤和慢性肾脏病等肾脏相关疾病。mRNA甲基化修饰逐渐成为诊断和监测人类肾脏疾病发生、发展的生物标志物。本文将对mRNA甲基化在各种人类肾脏疾病中的研究展开简要论述。 展开更多
关键词 mRnA甲基化 急性肾损伤 慢性肾脏病 n6-甲基腺苷 n1-甲基腺苷 n5-甲基胞苷
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关于n-纯同调维数的注记
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作者 吕家凤 金欣怡 《浙江师范大学学报(自然科学版)》 2024年第1期14-18,共5页
为了研究环与模的n-纯同调维数,通过同调的方法,分别给出了n-纯投射模与n-纯内射模的一些新刻画.作为应用,证明了环R的n-纯投射整体维数不超过1的充分必要条件是R的n-纯内射整体维数不超过1,得到了一个环R的n-纯投射整体维数与R的n-纯... 为了研究环与模的n-纯同调维数,通过同调的方法,分别给出了n-纯投射模与n-纯内射模的一些新刻画.作为应用,证明了环R的n-纯投射整体维数不超过1的充分必要条件是R的n-纯内射整体维数不超过1,得到了一个环R的n-纯投射整体维数与R的n-纯内射整体维数的对应关系. 展开更多
关键词 n-纯正合列 n-纯投射模 n-纯内射模 同调维数
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Exploring the effect of aggregation-induced emission on the excited state intramolecular proton transfer for a bis-imine derivative by quantum mechanics and our own n-layered integrated molecular orbital and molecular mechanics calculations
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作者 赵慧芳 孙朝范 +2 位作者 刘晓春 尹航 石英 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第1期645-649,共5页
We theoretically investigate the excited state intramolecular proton transfer(ESIPT) behavior of the novel fluorophore bis-imine derivative molecule HNP which was designed based on the intersection of 1-(hydrazonometh... We theoretically investigate the excited state intramolecular proton transfer(ESIPT) behavior of the novel fluorophore bis-imine derivative molecule HNP which was designed based on the intersection of 1-(hydrazonomethyl)-naphthalene-2-ol and 1-pyrenecarboxaldehyde. Especially, the density functional theory(DFT) and time-dependent density functional theory(TDDFT) methods for HNP monomer are introduced. Moreover, the "our own n-layered integrated molecular orbital and molecular mechanics"(ONIOM) method(TDDFT:universal force field(UFF)) is used to reveal the aggregation-induced emission(AIE) effect on the ESIPT process for HNP in crystal. Our results confirm that the ESIPT process happens upon the photoexcitation for the HNP monomer and HNP in crystal, which is distinctly monitored by the optimized geometric structures and the potential energy curves. In addition, the results of potential energy curves reveal that the ESIPT process in HNP will be promoted by the AIE effect. Furthermore, the highest occupied molecular orbital(HOMO) and lowest unoccupied molecular orbital(LUMO) for the HNP monomer and HNP in crystal have been calculated. The calculation demonstrates that the electron density decrease of proton donor caused by excitation promotes the ESIPT process. In addition, we find that the variation of atomic dipole moment corrected Hirshfeld population(ADCH) charge for proton acceptor induced by the AIE effect facilitates the ESIPT process. The results will be expected to deepen the understanding of ESIPT dynamics for luminophore under the AIE effect and provide insight into future design of high-efficient AIE compounds. 展开更多
关键词 time-dependent density functional theory(TDDFT) METHOD excited state intramolecular proton transfer(ESIPT) our own n-layered integrated MOLECULAR orbital and MOLECULAR mechanics(OnIOM) METHOD potential energy curves atomic dipole moment corrected Hirshfeld population(ADCH) charge
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