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Decadal expansion and contraction of permafrost in the Three-River Source Region,Qinghaie-Tibet Plateau(1901-2020)

Advances in Climate Change Research 2023年第2期14卷 226-236页

作者： fang-fang CHEN dong-Liang LUO Yi-Ting GAO Wen-Jie LEI State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China

Permafrost and its spatiotemporal variation considerably influence the surface and sub-surface hydrological processes,biogeochemical cycles,fauna and flora growth and cold region engineering projects in the Three-River Source Region(TRSR),Qinghai–Tibet ***,the dynamics of permafrost over a relatively long term duration(e.g.>100 years)in the TRSR is not well ***,the spatial and temporal variations of the temperature at the top of the perennially frozen/unfrozen ground(TTOP),active layer thickness(ALT)in permafrost regions and the maximum depth of frost penetration(MDFP)in the seasonally frozen ground of the TRSR during 1901–2020 were simulated using the TTOP model and Stefan equation driven by the widely used reanalysis Climatic Research Unit 4.05 *** revealed that the permafrost in the TRSR over the past 120 years did not degrade monotonically but experienced considerable fluctuations in area with the decadal oscillations of climate warming and cooling:shrinking from 263.9×10^(3)km^(2)in the 1900s to 233.3×10^(3)km^(2)in the 1930s,expanding from 232.3×10^(3)km^(2)in the 1940s to 260.9×10^(3)km^(2)in the 1970s and shrinking again from 254.1×10^(3)km^(2)in the 1980s to 228.9×10^(3)km^(2)in the *** regional average TTOP increased from−1.34±2.74℃in the 1910s to−0.48±2.69℃in the 2010s,demonstrating the most noticeable change for the extremely stable permafrost(TTOP3.0 m by 12%from 1901 to ***,minor changes were observed for the regional average MDFP,probably due to the increase in the area proportion of MDFP3.5 m(owing to the transformation of permafrost to seasonally frozen ground)by 7.39%and 4.77%,*** findings can facilitate an in-depth understanding of permafrost dynamics and thus provide a scientific reference for eco-environment protection and s

关键词： Three-River Source Region Permafrost TTOP model Stefan equation Qinghaie-Tibet Plateau

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Binding Energy of an Off-Center D^-in a Spherical Quantum Dot

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Communications in Theoretical Physics 2009年第5期51卷 919-922页

作者： LIU dong-Ming XIE Wen-fang Department of Physics College of Physics and Electronic Engineering Guangzhou University Guangzhou 510006 China

Using the method of matrix diagonalization, we investigate an off-center D^- in a spherical quantum dot （QD） subjected to a parabolic potential confinement. We discuss the effect of the position of an impurity in the QD on the binding energy of the D system, Eurthermore, we compare a negatively charged donor D^- with a neutral donor DO confined by a spherical QD with a parabolic potentiM. The results have clearly demonstrate the so-called quantum size effect. The binding energy is dependent on the confining potential hw0 and the impurity ion distance D.

关键词： quantum dots donor

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Discovery of a new family member of arsenic–vanadium polyoxometalates with high catalytic performance for one-pot coupling of CO2, epoxides and amines

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Tungsten 2025年第1期 80-87页

作者： fang-Qian Wang Yin Zhang Wei-Wei Wang Mei-Qian Fu Hong-Bing Mo Wei-dong Yu Chao Liu Jun Yan College of Chemistry and Chemical Engineering Central South University Junior Education Department Changsha Normal University School of Science Hunan University of Technology and Business

Arsenic-vanadium polyoxometalates（POMs） represent a family of tremendous potential catalysts owing to their peculiar physical and chemical *** in CO2conversion,using POMs to catalyze the conversion of CO2and epoxide into chemical intermediates is the research ***,A new family number of arsenic-vanadium POMs,[N（CH3）4]4[As8V12O38（H2O）]·2H2O({As8V12O38}),was reported and characterized by single-crystal X-ray diffraction,fourier transform infrared spectroscopy,X-ray photoelectron spectroscopy,*** from other allotropicity,{As8V12O38}shows a different structure pattern with an I-43d *** obtained {As8V12O38} was employed as a catalyst for the *** initial catalytic reaction confirmed that {As8V12O38} can catalyze the formation of epoxy carbonate by using 1.01 kPa CO2and epoxide at 70℃.Furtherly,when added amine in the catalytic system,oxazolidinone could be obtained by high yields,which provides an efficient way to convert CO2into profitable ***,a possible catalytic reaction mechanism was proposed by using different characterization analyses.{As8V12O38} first catalyzes the epoxide and CO2to form an epoxy carbonate and then catalyzes epoxy carbonate and benzylamine into oxazolidinone.

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2νββ-decay to first 2^+states with partial isospin symmetry restoration from spherical QRPA calculations

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Chinese Physics C 2020年第8期44卷 139-146页

作者： dong-Liang fang Amand Faessler Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China Center for Theoretical Physics Jilin UniversityChangchun 130012China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China Institute for Theoretical Physics Tuebingen UniversityD-72076Germany

Using partially restored isospin symmetry,we calculate the nuclear matrix elements for a special decay mode of a two-neutrino double beta decay–the decay to the first 2+excited *** the realistic CD–Bonn nuclear force,we analyze the dependence of the nuclear matrix elements on the isovector and isoscalar parts of proton–neutron particle–particle *** dependence on the different nuclear matrix elements is observed,and the results are *** also provide the phase space factors using numerical electron wavefunctions and properly chosen excitation ***,we present our results for the half-lives of this decay mode for different nuclei.

关键词： double beta decay quasi-particle random phase approximation nuclear matrix element

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Study on the performance of a large-size CsI detector for high energy γ-rays

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Nuclear Science and Techniques 2018年第1期29卷 58-64页

作者： He dong De-Qing fang Chen Li Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China University of Chinese Academy of Sciences Beijing 100049China

The measurement of high-energy γ-rays is an important experimental method to study the giant resonance in a nucleus, c reaction in nuclear astrophysics, and so on. The performance of a large-size Cs I detector for crays detection is studied by comparison between the experimental measurements and GEANT4 simulation. The reliability of the simulated efficiency for low-energy γ-rays is verified by comparing with the experimental data. The efficiency of the Cs I detector for high-energy γ-rays was obtained by the GEANT4 simulation. The simulation shows that the detection efficiency of 20 Me V γ-rays can reach 3.8%.

关键词： CsI:Tl Scintillation detector Full absorption efficiency Energy resolution GEANT4 simulation

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治糖保肾冲剂治疗早期糖尿病肾病大鼠的实验研究

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上海中医药大学学报 2000年第4期14卷 47-49页

作者：徐蓉娟李红唐红葛芳芳赵东杰上海中医药大学附属龙华医院内分泌科上海200032

为验证治糖保肾冲剂 (黄芪、丹参、山萸肉等 )对早期糖尿病肾病 (DN)的疗效并探讨其作用机理 ,采用多次腹腔注射链脲佐菌素 (STZ)建立早期DN大鼠模型 ,分别给予治糖保肾冲剂 (中药组 )、苯那普利 (西药组 )治疗 4周后 ,观察大鼠空腹血糖... 详细信息

为验证治糖保肾冲剂 (黄芪、丹参、山萸肉等 )对早期糖尿病肾病 (DN)的疗效并探讨其作用机理 ,采用多次腹腔注射链脲佐菌素 (STZ)建立早期DN大鼠模型 ,分别给予治糖保肾冲剂 (中药组 )、苯那普利 (西药组 )治疗 4周后 ,观察大鼠空腹血糖 (FPG)、糖化血红蛋白 (HbA1 C)、尿微量白蛋白 (UA1b)、尿转铁蛋白 (UTRF)、尿N 乙酰 β D 氨基葡萄糖苷酶 (UNAG)、尿α1微球蛋白 (Uα1 M)、血栓烷素B2 (TXB2 )、6酮前列腺素F1 α(6 keto PGF1 α)以及肾脏病理等的改善情况。结果 :中药组FPG、HbA1 C显著低于模型组 (P <0 .0 1)及西药组 (P <0 .0 5 ) ,TXB2及TXB2 / 6 keto PGF1 α也低于模型组及西药组 (P均 <0 .0 1) ,UA1b、UTRF、UNAG、Uα1 M等四项指标及肾重 /体重 (RW /BW )两治疗组均显著低于模型组 (P <0 .0 5～ 0 0 1) ,但中、西药组间无明显差异。提示治糖保肾冲剂能降低高血糖 ,降低尿微量蛋白 ,抑制血小板活化。

关键词：治糖保肾冲剂早期粮尿病肾病尿微量白蛋白

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认知-存在团体干预对肺癌化疗患者癌症复发恐惧感的影响

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广东医学 2018年第5期39卷 782-785页

作者：赵毛妮李秋芳吴秋歌崔芳芳王晓东崔妙然高亚娜郑州大学护理学院河南郑州450001 郑州大学第一附属医院呼吸内科一病区河南郑州450003 河南省肿瘤医院呼吸内科三病区河南郑州450008

目的探讨认知-存在团体干预(CE)对肺癌化疗患者癌症复发恐惧感(FCR)的影响。方法选取恐惧疾病进展量表(Fo P-Q-SF)得分≥24分的肺癌化疗患者94例,分为对照组(n=47)和干预组(n=47),对照组接受常规护理,干预组接受6次CE和4次电话随访,在... 详细信息

目的探讨认知-存在团体干预(CE)对肺癌化疗患者癌症复发恐惧感(FCR)的影响。方法选取恐惧疾病进展量表(Fo P-Q-SF)得分≥24分的肺癌化疗患者94例,分为对照组(n=47)和干预组(n=47),对照组接受常规护理,干预组接受6次CE和4次电话随访,在干预前和干预后使用Fo P-Q-SF、简明癌症患者心理适应状况问卷(Mini-MAC-19)评估干预效果。结果干预组患者在干预后,Fo P-Q-SF(23.49±3.28)分、Mini-MAC-19(31.72±2.86)分,其中无助/绝望(10.23±1.99)分,焦虑(7.66±1.58)分,积极态度(14.06±2.49)分,两组患者各项得分比较差异均有统计学意义(P<0.05)。结论 CE能够有效降低肺癌化疗患者的FCR水平,提高患者的心理适应能力,进而提高其生活质量。

关键词：认知肺癌恐惧

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Biodegradation of imazapyr in typical soils in Zhejiang Province,China

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Journal of Environmental Sciences 2005年第4期17卷 593-597页

作者： WANGXue-dong ZHOUSu-mei WANGHui-li FANDe-fang KeyLaboratoyofPesticideandChemicalBiology-MinistryofEducation CollegeofChemistryCentralChinaNormalUniversityWuhan430079 CollegeofAgronomy HenanAgriculturalUniversityZhengzhou450002China PesticidesandEnvironmentalToxicologyResearchInstitute ZhejiangUniversityHangzhou310029China

The degradation of imazapyr in non-sterile and sterile soils from four sampling sites in Zhejiang, China was studied. The results showed that the half-lives of imazapyr in non-sterile soils were in the range of 30 to 45 d, while 81 to 133 d in sterile(by autoclaving) soils. It means the rate constants of imazapyr under non-sterile conditions were 2 3—4 4 times faster than that under sterile(by autoclaving) conditions, evidently indicating that the indigenous microorganisms in soil play an important role in the degradation of imazapyr. The different sterilization methods could result in different degradation rates of imazapyr. The heat of sterilization of soil largely decreased the degradation. However, the sterile treatment of soil by sodium azide had a different effect from that by autoclaving. Further more, the mechanism was also discussed. Biodegradation in four non-sterile soils accounted for 62% to 78% of imazapyr degradation. In contrast, less than 39% of imazapyr degradation was associated with chemical mechanisms. Therefore, the degradation mechanism was predominantly involved in biology including organisms and microorganisms in soil. Two imazapyr-degrading bacterial strains were isolated in enrichment culture technique and they were identified as Pseudomonas fluorescenes biotypeⅡ(ZJX-5) and Bacillus cereus(ZJX-9), respectively. When added at a concentration of 50 μg/g in mineral salts medium(MSM), ZJX-5 and ZJX-9 could degrade 81% and 87% imazapyr after 48 h of incubation. For the treatment of incorporation of ZJX-5 or ZJX-9 into soil, the degradation rate enhanced 3—4 fold faster than that for control samples, which showed an important value in quick decontamination of imazapyr in soil.

关键词： biodegradation imazapyr sterile soil non-sterile soil imazapyr-degrading bacteria

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Control of Titanium Alloy Thin Plate Welding Distortion by Trailing Peening

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Journal of Materials Science & Technology 2003年第z1期19卷 184-186页

作者： Xuesong LIU Hongyuan fang Shude JI Zhibo dong State Key Laboratory of Advanced Welding Production Technology Harbin Institute of TechnologyHarbin 150001 China State Key Laboratory of Advanced Welding Production Technology Harbin Institute of TechnologyHarbin 150001 China State Key Laboratory of Advanced Welding Production Technology Harbin Institute of TechnologyHarbin 150001 China State Key Laboratory of Advanced Welding Production Technology Harbin Institute of TechnologyHarbin 150001 China

The technology of trailing peening is a kind of promisingly bran-new technology which can be used to control weldingstress and distortion of Ti alloy thin plate. Control of TC4 Ti alloy thn plate welding stress and distortion underthe condition of conventional welding and trailing peening is performed, respectively. The results show that thetechnology of trailing peening effectively reduces deflection and transverse shrinkage of thin plate weldment. Themaximum deflection is decreased from 15 mm under the conditior of conventional welding to 5 mm, while the weldtransverse shrinkage is decreased from 0.5 mm to about 0.1 mm.

关键词： Control of residual stress and distortion, Trailing peening, TC4 Ti alloy

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Integrated Entry Guidance for Reusable Launch Vehicle

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Chinese Journal of Aeronautics 2007年第1期20卷 1-8页

作者： NING Guo-dong ZHANG Shu-guang fang Zhen-ping School of Aeronautical Science and Technology Beijing University of Aeronautics and Astronautics Beijing 100083 China

A method for the implementation of integrated three-degree-of-freedom constrained entry guidance for reusable launch vehicle is presented. Given any feasible entry conditions, terminal area energy management interface conditions, and the reference trajectory generated onboard then, the method can generate a longitudinal guidance profile rapidly, featuring linear quadratic regular method and a proportional-integral-derivative tracking law with time-varying gains, which satisfies all the entry corridor constraints and meets the requirements with high precision. Afterwards, by utilizing special features of crossrange parameter, establishing bank-reversal corridor, and determining bank-reversals according to dynamically adjusted method, the algorithm enables the lateral entry guidance system to fly a wide range of missions and provides reliable and good performance in the presence of significant aerodynamic modeling uncertainty. Fast trajectory guidance profiles and simulations with a reusable launch vehicle model for various missions and aerodynamic uncertainties are presented to demonstrate the capacity and reliability of this method.

关键词： guidance trajectory generation entry onboard constraint robustness

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