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国外特种经济动植物 1993年第3期 37-39页

作者： derr,jn 王大川

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桃李园,南京,江苏,中国

世界建筑 2024年第3期 72-73页

作者：蒋楠张准马杰睿孙嬿许悦高亦超张菁 SEUARCH-jn STUDIO(绘图) 侯博文(摄影) 东南大学建筑学院东南大学建筑设计研究院有限公司不详

桃李园位于百年老校的两栋文物建筑之间,西侧紧邻城市街道,通过历史/场所/建筑/结构/园林/身体的一体化实验和全专业融合,打破改造前的封闭沉闷形象,形成集校园次入口、活动、教育、展示、休闲、景观、观影等多功能于一体的现代园林小筑。

关键词：现代园林专业融合百年老校多功能街道

基于Meta分析的煤矿区植被恢复对土壤有机碳储量的影响

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环境科学 2024年第3期45卷 1629-1643页

作者：李健明康雨欣蒋福祯宋明丹祁凯斌卢素锦李正鹏青海大学农林科学院西宁810016 青海大学生态环境工程学院西宁810016

煤矿开采是全世界应对不断增加的能源需求的主要手段.但随着煤矿开采,区域生态系统遭到不同程度的破坏,导致“碳汇”能力下降.植被恢复是矿区退化的生态系统和固碳功能恢复的基础.然而,目前尚未对全球范围内煤矿区植被恢复对土壤有机碳(... 详细信息

煤矿开采是全世界应对不断增加的能源需求的主要手段.但随着煤矿开采,区域生态系统遭到不同程度的破坏,导致“碳汇”能力下降.植被恢复是矿区退化的生态系统和固碳功能恢复的基础.然而,目前尚未对全球范围内煤矿区植被恢复对土壤有机碳(SOC)的影响进行系统研究,因此无法准确预测全球SOC库对植被恢复的响应.通过搜集同行评议的112篇文章中植被恢复的土壤理化性质,以评估煤矿区植被恢复类型、土壤深度、恢复年份、年均温、年降水量和海拔等对SOC的影响,并明确相关的关键驱动因素.结果表明,受损煤矿区通过植被恢复能够显著改善土壤的理化性质,植被恢复后土壤相较于未恢复或自然恢复SOC储量提升了39.02%.当不考虑环境因素时,利于SOC储量积累的植被恢复类型为:农田>林地>草地>灌木林. 4种类型的植被恢复对表层(0~20 cm)SOC储量均得到显著增加,草地和灌木能显著增加深层(>40 cm)的SOC储量,而林地和农田类型下深层的SOC储量与未恢复或自然恢复后的SOC储量无显著差异.植被恢复后SOC储量的增加趋势会随着土壤深度的增加而降低.具体的植被恢复策略应根据气候条件选择合适的植被类型.受损煤矿区在年均温15℃和年降水量>800 mm的环境下,林地和农田恢复类型能够更好地增加SOC储量. TN、 BD、 AN和AK是影响土壤固碳能力的主要因素.研究可为量化受损煤矿区不同植被恢复措施的固碳效果和退化生态系统的恢复与重建提供理论参考.

关键词：煤矿区植被恢复土壤有机碳储量土壤特性森林草地农田灌木林

Structural Characterization and Chemical Modification of a Glucan from Spores of Ganoderma lucidum

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Chinese Chemical Letters 2001年第11期12卷 967-970页

作者： Bao, XF Fang, jn Chinese Acad Sci Shanghai Inst Biol Sci Shanghai Inst Mat Med Shanghai 200031 Peoples R China

A linear alpha -D-(1-->3)-glucan, named PSG, was obtained from the spores of Ganoderma lucidum. The synthesis of positively and negatively charged polyelectrolytes from PSG was developed. Amine groups and carboxymethyl groups were introduced through nucleophilic substitution with 3-chloropropylamine or chloroacetic acid, respectively, Reaction conditions were varied to obtain insight into the influence of variables on the degree of substitution.

关键词： alpha-D-(1 -> 3)-glucan chemical modification aminopropylation carboxymethylation

Investigation on the Microstructure Homogenization in a TiAl Based Alloy Prepared by Elemental Powder Metallurgy

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Journal of Materials Science & Technology 1999年第6期15卷 527-530页

作者： Liu, Y Huang, BY He, YH Wang, jn Cent S Univ Natl Key Lab Powder Met Changsha 410083 Hunan Peoples R China

A Ti-48Al (at. pet) alloy prepared by elemental powder metallurgy (EPM) has been heat treated under various conditions. Through optical and scanning electronic microscopy, EDAX, XRD analysis, and DTA, it was shown that the hot pressed microstructure consisted of alpha(2)-Ti3Al and TiAl phases. The alpha(2)-Ti3Al phase was island-like, and had a high stability and heredity in subsequent heat treatments. The supersaturation of Al in the island-like alpha-Ti3Al phase strongly influenced the transformation of alpha(or alpha(2)) to alpha(2)/gamma lamellar colonies. After a heat treatment at 1380 degrees C for 0.5 h and 1000 degrees C for 8 h, a fully lamellar microstructure with a colony size of 50 mu m was obtained. This result indicates that a homogeneous composition and an equilibrium microstructure in EPM TiAl-base alloys can only be obtained after heat treatment at temperatures above alpha transus temperature (T-alpha).

关键词： Titanium alloys

A Numerical Model for Typhoon Surges

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China Ocean Engineering 1998年第2期13卷 191-202页

作者： Pan, jn Wang, HC Yao, GQ Nanjing Hydraul Res Inst River Harbour Dept Nanjing 210024 Peoples R China

In this paper a simple and efficient implicit finite-difference scheme is used for depth-averaged two-dimensional storm surge model. This finite-difference scheme is simpler and more efficient than the widely-used ADI scheme. Accuracy analysis and stability analysis indicate that the scheme has two-order accuracy and is unconditionally stable when the grid size is constant. The present analysis results show that the scheme is of higher numerical accuracy than that introduced by Maa (1990). After tested by ideal models, a calculation example of a real typhoon surge is carried out, the results of the numerical simulation coincide well with the observed data and the accuracy is sufficient for engineering applications.

关键词： storm surge numerical simulation finite-difference scheme accuracy stability

FLOW　INJECTION　SPECTROPHOTOMETRIC　DETERMINATION　OF　VITAMIN　B_1　AND　VITAMIN　B_2　IN　MULTIVITAMIN

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Chinese Chemical Letters 1995年第8期6卷 705-706页

作者： Chang, H Yang, jn Fushun Petr Inst Petrochem Dept Fushun 113001 Peoples R China Liaoning Univ Dept Chem Shenyang 110036 Peoples R China

Vitamin B1 reacts with diazo-aminobenzene sulfonic acid to form a red complex in a basic mcdium and there is absorption of vitamin B2 at 440 nm. A flow injection lspectrophotometric determination of the two medicaments is described based on these *** method was simple and a high selecuivity and sampling rate of 60 *** dynamic linear ranges were 0-100 μg ml-1 of vitamin B1 and 0-80 μ g ml-1 of vitamin B2,*** relative standard deviation was 0.2881%(n=10)for vitamin B1.

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Retention Behaviors of Uronic Acid-containing Polysaccharides and Neutral Polysaccharides in HPGPC

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Chinese Chemical Letters 2001年第10期12卷 909-912页

作者： Liu, CP Bao, XF Fang, jn Chinese Acad Sci Shanghai Inst Biol Sci Shanghai Inst Mat Med Shanghai 200031 Peoples R China

The Chromatographic behaviors of several uronic acid-containing polysaccharides and neutral polysaccharides were investigated in HPGPC for the first time. The effects of sample concentration and ionic strength of mobile phase on retention time were studied. The mechanism for the effects on Mw determination results of polysaccharides by HPGPC was also discussed.

关键词： polysaccharides HPGPC molecular weights

Scale dependence of tensile strength of micromachined polysilicon MEMS structures due to microstructural and dimensional constraints

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Chinese Science Bulletin 2001年第16期46卷 1392-1397页

作者： Ding, jn Meng, YG Wen, SH Tsing Hua Univ Natl Tribol Lab Beijing 100084 Peoples R China

The success of microelectromechanical systems (MEMS) as a key technology in the 21st century depends in no small part on the solution of materials issues associated with the design and fabrication of complex MEMS devices. The reliable mechanical properties of these thin films are critical to the safety and functioning of these microdevices and should be accurately determined. In order to accomplish a reliable mechanical design of MEMS, a new microtensile test device using a magnetic-solenoid force actuator was developed to evaluate the mechanical properties of microfabricated polysilicon thin films with dimensions of 100—660 mm length, 20—200 mm width, and 2.4 mm thickness. It was found that the measured average value of Young抯 modulus, 164±1.2 GPa, falls within the theoretical bounds. The average fracture strength is 1.36 GPa with a standarddeviation of 0.14 GPa, and the Weibull modulus is 10.4—11.7, respectively. Statistical analysis of the specimen size effect on the tensile strength predicated the size effect on the length, the surface area and the volume of the specimens due tomicrostructural and dimensional constraints. The fracturestrength increases with the increase of the ratio of surfacearea to volume. In such cases the size effect can be tracedback to the ratio of surface area to volume as the governing parameter. The test data account for the uncertainties inmechanical properties and may be used in the future reliability design of polysilicon MEMS. The testing of 40specimens to failure results in a recommendation for design that the nominal strain be maintained below 0.0057.

关键词： microelectromechanical systems polysilicon elasticmodulus tensile strength size effect.

AN ITERATION METHOD FOR INCOMPRESSIBLEVISCOUS/INVISCID COUPLED PROBLEM VIA A SPECTRALAPPROXIMATION

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Journal of Computational Mathematics 1999年第4期17卷 379-396页

作者： Chuan-jn Xu(Department of Mathematics, Xiamen University, Xiamen 361005, China) 厦门大学数学系福建厦门 361005

An efficient iteration-by-subdomain method (known as the Schwarz alternating algorithm) for incompressible viscous/inviscid coupled model is presented. Appropriate spectral collocation approximations are proposed. The convergence analysis show that the iterative algorithms converge with a rate independent of the polynomial degree used.

关键词： coupled equations Navier-Stokes equations Euler equations cllocation approximation Schwarz alternating algorithm