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Kinetics of Phosphate Release from Three Phosphate-Treated Soils

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Pedosphere 2005年第4期15卷 518-525页

作者： LI Shou-tian ZHOU Jian-min wang Huo-Yan DU Chang-Wen CHEN Xiao-Qin Institute of Soil Science Chinese Academy of Sciences P. O. Box 821 Nanjing 210008 （China）.

Phosphate release from three selected soils after treatments of 1.6 and 2.4 mmol L-1 P was investigated using sequential extractions and fitted using six kinetic models, including zero order (Z), first order (F), second order (S), parabolic diffusion (PD), two constant rate (TC), and Elovich type (ET) equations. The results showed that the rate of P release was initially rapid and then gradually declined with time. Also, P release increased with added P. Total P release followed the order: paddy soil with 2.4 mmol L-1 P > red soil with 2.4 mmol L-1 P > paddy soil with 1.6 mmol L-1 P > fluvo-aquic soil with 2.4 mmol L-1 P > fluvo-aquic with 1.6 mmol L-1 P > red soil with 1.6 mmol L-1 P. For the two P treatments P release from the paddy soils in the first extraction was 44.3% and 45.6% of total released P, respectively, which were higher than those from red and fluvo-aquic soils. The ratio of P release at the end of release time was 14.0% and 13.1% in the paddy soil treated with 1.6 and 2.4 mmol L-1 P, respectively, but only 5.1% and 9.2% in the red soil and 7.0% and 5.2% in the fluvo-aquic soil, respectively. Comparison of the coefficients of determination (R2) indicated that ET, TC, and PD equations could describe the P release data better than Z, F, and S equations.

关键词： fluvo-aquic soil paddy soil phosphate red soil release kinetics

Synthesis of magnetic core-shell iron nanochains for potential applications in Cr(Ⅵ)ion pollution treatment

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Rare Metals 2021年第1期40卷 176-179页

作者： Hai-Feng Feng You-Xing Yu Shi-Qi Jiang Jun Shang Yan Cheng Liang wang Wei-Chang Hao tian-min wang , School of Materials Science and Engineering Beihang UniversityBeijing 100191China Center of Materials Physics and Chemistry and Department of Physics Beihang UniversityBeijing 100191China

Fe nanochains with diameters of 50-150 nm and average length of about 1μm were synthesized by titrating NaBH_(4)solution into FeCl_(2) aqueous solution(i.e.,reduction of Fe(II)ions).The microstructures and magnetic properties were studied by X-ray diffraction(XRD),transmission electron microscope(TEM),and vibrating sample magnetometer(VSM).The results reveal that the nanochains have a core-shell structure with a-Fe as the core and amorphous iron oxide as the *** Fe coreshell nanochains show the characteristic of soft magnetic materials,achieving the highest magnetization of200.74 mA-m^(2)·g^(-1).The influences of the titrating rate of NaBH_(4)aqueous solution on the morphology of the Fe nanochains were also *** reveals that low titrating rate is beneficial for synthesizing Fe nanochains with uniform *** reduction experiments indicate that these Fe nanochains are of high *** 90%Cr(VI)ions are successfully removed after 10 min reaction of 100 mg Fe nanochains in the 100 ml K_(2)Cr_(2)O_(7) solution(100 mg·L^(-1))and more than 99%after 30 min.

关键词： Fe nanochains Core-shell structure Magnetic properties Reduction of Cr(Ⅵ)ion

SYNTHESIS OF DBA-VPI-5 AND ITS PHASE TRANSFORMATION

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Chinese Chemical Letters 1991年第12期2卷 979-982页

作者： Wen Tong tian Li min wang Shi Lun QIU Wen Qin PANG Department of Chemistry, Jilin University, Changchun, 130023

New synthetic condition in a wide temperature range from 110℃ to 190℃ was employed to crystallize DBA-VPI-5. The phase transformation of the samples prepared at different temperatures was measured by high-temperatur... 详细信息

关键词： VPI SYNTHESIS OF DBA-VPI-5 AND ITS PHASE TRANSFORMATION DBA ITS

Construction of a lentiviral vector for RNA interference of human VIM gene and its silencing effect in pancreatic cancer cells

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The Chinese-German Journal of Clinical Oncology 2009年第3期8卷 145-149页

作者： Jianxin Jiang ming Shen Renyi Qin Rui tian Jing Li min wang Department of Biliary-Pancreatic Surgery Tongji Hospital Tongji Medical College Huazhong University of Scienceand Technology Wuhan 430030 China

Objective： To construct a lentiviral expression vector for RNA interference （RNAi） of human VIM gene; and assess its gene silencing effect in pancreatic cancer cell line Panc-1. Methods： Three pairs of human VIM gene short hairpin RNA（shRNA） sequences were designed using a software available on-line and one pair came from document. After synthesis and annealing, four double-stranded oligonucleotides （dsOligo） were cloned into the pGCL-GFP/U6 plasmid, which were subsequently confirmed by polymerase chain reaction （PCR） and DNA sequencing analysis. Real-time PCR and Westemblotting were used to screen the effective pGCL-GFP-shRNA plasmid in 293T cells, then the most effective one was packed into the recombinant lentivirus Lv-VIM-shRNA with lentiviral packing materials pHelper 1.0 and pHelper 2.0 in 293T cells. The titer of lentivirus was determined by hole-by-dilution titer assay. The silencing effect of Lv-VIM-shRNA in Panc-1 calls were validated by real-time PCR and Western-blotting. Results： An effective Lv-VIM-shRNA was successfully constructed. The titer of lentivirus was determined on 2× 10^9TU/mL. The expressions of VIM mRNA and vimentin were down-regluated in the Panc-1 cells infected with Lv-VIM-shRNA. Conclusion： An effective Lv-VIM-shRNA could inhibit the expression of VIM gene in Panc-1 cells in vitro, which provides a tool for investigating the role of VIM gene in the signaling pathway involved in tumorigenesis and progression of pancreatic cancer and searching new therapeutic targets.

关键词： vimentin RNA interference lentivirus pancreatic carcinoma

Enhancement of magnetism of Zn0.95Co0.05O films by p-type Cu+ doping

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Progress in Natural Science:Materials International 2011年第1期21卷 31-35页

作者： Wei-chang HAO~(1,5),Jian-jun LI~2,Huai-zhe XU~3,Jia-ou wang~4,tian-min wang~1 1.Center of Materials Physics and Chemistry,Beihang University,Beijing 100083,China 2.Department of Materials Science and Engineering, Anhui University of Science and Technology,Huainan 232001,China 3.Department of Physics,Beihang University,Beijing 100083,China 4.Beijing Synchrotron Radiation Facility,Institute of High Energy Physics, Chinese Academy of Sciences,100049,China 5.Key Laboratory of Micro-nano Measurement,Manipulation and Physics, ministry of Education,Beihang University,Beijing 100191,China [a] Center of Materials Physics and Chemistry Beihang University Beijing 100083 China [b] Department of Materials Science and Engineering Anhui University of Science and Technology Huainan 232001 China [c] Department of Physics Beihang University Beijing 100083 China [d] Beijing Synchrotron Radiation Facility Institute of High Energy Physics Chinese Academy of Sciences 100049 China [e] Key Laboratory of Micro-nano Measurement Manipulation and Physics Ministry of Education Beihang University Beijing 100191 China

Zn0.95Co0.05O and Zn0.91Co0.05Cu0.04O thin films were fabricated on Si（111） substrate by the reactive magnetron sputtering method at different O-Ar *** characterizations by X-ray diffractometry（XRD）,X-ray photo-electronic spectrum（XPS）, and electron paramagnetic resonance（EPR） indicate that the doped Cu ions substitute the Zn2+ions in the ZnO *** doped Cu ions are in Cu+and Cu2+mixture valence *** ferromagnetism of the Zn0.91Co0.05Cu0.04O film increases gradually the increasing Cu+ions *** results indicate that the increase of ferromagnetism is not owing to the magnetic contribution of Cu+ions themselves,but owing to the enhancement of magnetic interaction between Co ions,which suggests that p-type doping of Cu+ions plays an important role in mediating the ferromagnetic coupling between Co ions.

关键词： Zn0.95Co0.05O films Zn0.91Co0.05Cu0.04O films magnetic semiconductors magnetic coupling co-doping

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面向掘进性能的盾构刀盘系统设计方法研究

机械设计 2017年第9期34卷 72-78页

作者：武力关天民王广欣张佳媛马克大连交通大学机械工程学院辽宁大连116028

提出了盾构刀盘系统设计和评价方法的理论框架,重点阐述了刀盘系统设计流程。采用经验公式和理论分析的方法,面向刀盘系统的排土率、掘进面稳定性、刀具寿命、刀盘功率和结构性能,给出了刀盘系统设计的流程。以北京地铁4号线角门北路站... 详细信息

提出了盾构刀盘系统设计和评价方法的理论框架,重点阐述了刀盘系统设计流程。采用经验公式和理论分析的方法,面向刀盘系统的排土率、掘进面稳定性、刀具寿命、刀盘功率和结构性能,给出了刀盘系统设计的流程。以北京地铁4号线角门北路站—北京南站区间路段为背景,设计出相适应的刀盘结构参数、刀具布置和操作控制参数。该设计结果与实际使用刀盘结构相似,说明设计流程可行。

关键词：刀盘系统设计方法掘进性能盾构

Study of Surface Cell Madelung Constant and Surface Free Energy of Nanosized Crystal Grain

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Chinese Journal of Structural Chemistry 2005年第12期24卷 1369-1374页

作者： ZHANG Wei-Jia wang tian-min CUI min School of Science Beijng University of Aeronutics and Astronautics Beijing 100083 China

Surface cell Madelung constant is firstly defined in calculating surface free energy of nanosized crystal grains, which explains the physical performance of small crystals and may be great benefit to make surface analysis and study dynamics of crystal nucleus growth. A new approximative expression of surface energy and relevant thermodynamic data was used in this calculation. A new formula and computing method for calculating the Madelung constant a of any complex crystals is proposed, and surface free energies and surface electrostatic energies of nanosized crystal grains as well as Madelung constant of some complex crystals are theoretically calculated in this paper. The surface free energy of nanosized crystal grain TiO2 and surface electrostatic energy（absolute value） of nanosized crystal grain α-A12O3 are found to be the biggest among other crystal grains.

关键词： Madelung constant surface free energy nanosized crystal grain

不同土壤磷的固定特征及磷释放量和释放率的研究

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土壤学报 2003年第6期40卷 908-914页

作者：李寿田周健民王火焰陈小琴杜昌文中国科学院南京土壤研究所南京210008

通过加入不同浓度的P(水土比为 2 0∶1 )并利用连续提取法 ,对三种土壤P的固定特征以及磷的释放进行了研究。结果表明 ,红壤对P的固定能力高于潮土 ,而潮土高于水稻土 ,在加入P量为 2 97gkg- 1土壤的条件下 ,三种土壤对P的固定量分别为... 详细信息

通过加入不同浓度的P(水土比为 2 0∶1 )并利用连续提取法 ,对三种土壤P的固定特征以及磷的释放进行了研究。结果表明 ,红壤对P的固定能力高于潮土 ,而潮土高于水稻土 ,在加入P量为 2 97gkg- 1土壤的条件下 ,三种土壤对P的固定量分别为 2 84gkg- 1、2 5 3gkg- 1和 2 0 8gkg- 1。三种土壤对P的固定率则随着加入P量的增加而降低。在P的释放研究中 ,随着提取次数的增加 ,P的释放量减少 ,并在提取 8次后 ,以后各次P的释放量不发生显著变化。三种土壤中 ,水稻土P的最大释放量 (1 2 4 0 7mgkg- 1)显著高于红壤 (60 46mgkg- 1)和潮土 (1 9 74mgkg- 1) ,水稻土P的总释放量 (1 6次 )也大于红壤和潮土 ,三种土壤P的总释放量分别为 2 0 6 0 2 (1 98gkg- 1土壤P处理 )和 2 71 91mgkg- 1(2 97gkg- 1土壤P处理 )、1 0 0 48和2 60 5 3mgkg- 1、1 1 6 0 6和 1 3 1 91mgkg- 1。三种土壤P的释放率随着提取次数的增加而增加 ,并逐渐达到稳定。水稻土的释放率显著高于红壤和潮土。水稻土和潮土中 ,1 98gkg- 1土壤P处理的土壤P的释放率高于2 97gkg- 1土壤P处理的土壤。

关键词：土壤磷固定特征磷释放量释放率连续提取法

循环排列的增强型绿色荧光蛋白的构建及性能表征

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南宁师范大学学报(自然科学版) 2025年第1期42卷 86-93页

作者：王丹宋天宇韦敏南宁师范大学化学与材料学院南宁新技术创业者中心

荧光蛋白的自催化稳健荧光和无细胞毒性特性，使其成为监测细胞内信号分子的关键工具。然而，循环排列的荧光蛋白（Circularly Permuted Fluorescent Proteins,cpFPs）仍存在着自身强度弱和无法适用于复杂细胞环境内检测等问题，因此，... 详细信息

荧光蛋白的自催化稳健荧光和无细胞毒性特性，使其成为监测细胞内信号分子的关键工具。然而，循环排列的荧光蛋白（Circularly Permuted Fluorescent Proteins,cpFPs）仍存在着自身强度弱和无法适用于复杂细胞环境内检测等问题，因此，获得更多类型的循环排列荧光蛋白并研究其光学活性和物理性能具有重要意义。构建一种新型的循环排列荧光蛋白——cpEGFP，并探究不同温度下cpEGFP在Escherichia coli BL21菌株的表达效果，同时比较其与超折叠绿色荧光蛋白（sfGFP）的光学特性，发现cpEGFP的发色团环境已经被改变，且荧光寿命有所延长。另外，尽管cpEGFP具有可观的荧光强度，但其亮度及量子产率比sfGFP都有所降低，后续需要进一步对其性能进行优化。研究结果为循环排列荧光蛋白cpEGFP的性能优化以及在细胞内信号分子检测中的应用奠定了基础，对于发展更为高效、特异的荧光探针具有重要意义。

关键词：循环排列绿色荧光蛋白超折叠绿色荧光蛋白诱导表达相对荧光量子产率荧光寿命

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