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Solvothermal Synthesis and Crystal Structure of Zn(en)_3B_5O_7(OH)_3

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Chemical Research in Chinese Universities 2006年第3期22卷 271-273页

作者： HE yi chen wei YANG Jin XI Chun-yu chen Jie-sheng State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of Chemistry Jilin University Changchun 130012 P. R. China

A new polyborate containing ehiral metal-complex Zn（en）3 B5O7（OH）3, where en = ethylenediamine, was synthesizedunder solvothermal conditions and structurally characterized by means of X-ray diffraction analysis. Crystal data： Zn（en）3 B5O7（OH）3, monoclinic, space group P21/c, a =0.8532（72） nm, b =2.3340（5） nm, c = 0.9526（92） nm, β =107. 04（3）°, Z=4, V=1.8140（6） nm^3, Dc =1.694 g/cm^3, p=1.416 mm^-1, F（000） = 960, GOF = 1. 020, R =0. 0276, Rw =0. 0828. There is a chiral Zn（en）3^2＋ complex cation and an isolated B5O7（OH）3^2- group in a Zn（en）3 B5O7（OH）3 molecule. The enantiomer of the chiral complex cation is separated orderly as ,4 and A configurations in the compound and the borate group consists of two B303 cycles linked through a bridging boron atom.

关键词： Solvothermal synthesis Crystal structure Chiral metal-complex Borate compound

Flow Behavior Behind A Freely Suspended Cylinder in the Wake of A Stationary Cylinder

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China Ocean Engineering 2020年第5期34卷 708-717页

作者： GAO Yang-yang chen wei-yi TAN Soon Keat ZHANG Bao-feng Ocean College Zhejiang UniversityZhoushan 316021China Maritime Research Centre School of Civil Environmental EngineeringNanyang Technological University639798Singapore Powerchina Huadong Engineering Corporation Limited Hangzhou 311122China

The experiment of flow past a freely suspended circular cylinder in the wake of an upstream stationary cylinder was carried out in a re-circulating water channel using the Particle Image Velocimetry(PIV) technique. The upstream cylinder was fixed, while the downstream cylinder was suspended from a platform and allowed to move freely in the horizontal plane. The centre-to-centre spacing ratio between two tandem cylinders was initially kept at a constant value of 3.0. The instantaneous flow field and the orbital trajectories were analyzed to reveal the effect of the presence of the upstream cylinder and flow velocity on the dynamic response of the downstream suspended *** results showed that the upstream stationary cylinder has significant effect on modifying the flow patterns behind two tandem cylinders. Different trajectories of the downstream suspended cylinder with variation of flow velocity U were observed, such as:(1) depicting a figure-8 type motion at U = 0.27 m/s;(2) undergoing intermittent oscillations as it travels downstream at 0.3 m/s ≤ U ≤ 0.37 m/s;(3) successive moving downstream, no obvious streamwise oscillation observed at U = 0.43 m/s.

关键词： downstream suspended cylinder PIV camera orbital response flow pattern

Least trace extended set-membership filter

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Science China(Information Sciences) 2010年第2期53卷 258-270页

作者： HUANG yi , chen ZongJi & wei chen National Key Laboratory of Science and Technology on Integrated Control Technology, School of Automation Science and Electric Engineering, Beihang University, Beijing 100083, China National Key Laboratory of Science and Technology on Integrated Control Technology School of Automation Science and Electric Engineering Beihang University Beijing China

To improve the consistency of estimation result, a least-trace extended set-membership filter (LTESMF) is presented for a class of nonlinear stochastic systems, which has linear output and unknown- but-bounded noise. Feedback technique is used instead of the intersection of ellipsoid-sets in the measurement update. The feedback parameter is optimized in order to minimize the trace of error bounded ellipsoid’s envelop matrix. A new stability analysis method was developed to prove the stochastic system’s stability by using the convergence of some measurement of the error bounded ellipsoid. Analysis result shows that the estimation error of LTESMF will converge to a bounded area. A simulation of SINS/GPS integrated alignment with large misalignment angles is conducted. The results demonstrate that the convergence speed and the consistency of LTESMF are much better than those of extended Kalman filter (EKF), in addition the steady estimation precision and computational complexity are close to that of EKF.

关键词： set-membership estimation nonlinear system convergence upper bound least trace stability analysis

Modified partially wide tangents technique in post-mastectomy radiotherapy for patients with left-sided breast cancer

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Chinese Medical Journal 2010年第20期123卷 2825-2831页

作者： ZHANG Qian chen Jia-yi HU wei-gang GUO Xiao-mao Department of Radiation Oncology Fudan University Shanghai Cancer Center Department of Oncology Shanghai Medical CollegeFudan UniversityShanghai 200032China

Background The role of internal mammary nodes （IMN） irradiation for breast cancer patients after mastectomy remains controversial. This study aimed to compare different techniques for radiation of the chest wall （CW） and IMN post-mastectomy for left-breast cancer patients in terms of dose homogeneity within planning target volume （PTV） and dose to critical *** Thirty patients underwent CT simulation, while CW, IMN, left lung, heart and contralateral breast were contoured. Three three-dimensional conformal radiotherapy （3D-CRT） techniques, namely, standard tangents, partially wide tangents （PWT）, and modified PWT techniques plus intensity modulated radiotherapy （IMRT） technique have been used to radiate CW and IMN. In addition to the target coverage and dose homogeneity, we also evaluated the dose to the critical structures including heart, left lung and contralateral *** All three 3D-CRT techniques provided satisfactory coverage regarding total PTV. The PWT and the modified PWT gave better coverage of IMN PTV with V47.5 of （96.83±4.56）% and （95.19±3.90）% compared to standard tangents （（88.16±7.77）%）, P 〈0.05. The standard tangents also contributed the biggest IMN VD105%, VD110%, VD115% and VD120%. The lowest mean dose of the heart was achieved by the modified PWT （（8.47±2.30） Gy）, compared with PWT （（11.97±3.54）Gy） and standard tangents （（11.18±2.53） Gy）. The mean dose of lung and contralateral breast with the modified PWT was significantly lower than those with PWT. Comparing IMRT with the modified PWT, both techniques provided satisfactory coverage. The conformity indexes （CI） with IMRT （CI1： 0.71±0.02; CI2： 0.64±0.02） were better than those with the modified PWT （CI1： 0.50±0.02; CI2： 0.45±0.02）. The mean dose, V5, V10 and V5-10 of heart and left lung with the modified PWT were significantly lower than those with the IMRT. The mean dose and VD2% of contralateral breast with the modified PWT were not significantly different from the IMRT （

关键词： breast cancer internal mammary nodes postmastectomy radiotherapy intensity modulated radiotherapy

PI3K/AKT signaling and neuroprotection in ischemic stroke:molecular mechanisms and therapeutic perspectives

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Neural Regeneration Research 2025年第10期20卷 2758-2775页

作者： Tianlong Liu Xiaolin Li Xiaowei Zhou wei chen Aidong Wen Minna Liu yi Ding Department of Pharmacy Xijing HospitalFourth Military Medical UniversityXi’anShaanxi ProvinceChina Department of Pharmacy The 940 Hospital of Joint Logistics Support Forces of Chinese PLALanzhouGansu ProvinceChina Department of Pharmacy The 944 Hospital of Joint Logistics Support Forces of Chinese PLAJiuquanGansu ProvinceChina Department of Nephrology The 940 Hospital of Joint Logistics Support Forces of Chinese PLALanzhouGansu ProvinceChina

It has been reported that the PI3K/AKT signaling pathway plays a key role in the pathogenesis of ischemic *** a result,the development of drugs targeting the PI3K/AKT signaling pathway has attracted increasing attention from *** article reviews the pathological mechanisms and advancements in research related to the signaling pathways in ischemic stroke,with a focus on the PI3K/AKT signaling *** key findings include the following:(1)The complex pathological mechanisms of ischemic stroke can be categorized into five major types:excitatory amino acid toxicity,Ca^(2+)overload,inflammatory response,oxidative stress,and apoptosis.(2)The PI3K/AKT-mediated signaling pathway is closely associated with the occurrence and progression of ischemic stroke,which primarily involves the NF-κB,NRF2,BCL-2,mTOR,and endothelial NOS signaling pathways.(3)Natural products,including flavonoids,quinones,alkaloids,phenylpropanoids,phenols,terpenoids,and iridoids,show great potential as candidate substances for the development of innovative anti-stroke medications.(4)Recently,novel therapeutic techniques,such as electroacupuncture and mesenchymal stem cell therapy,have demonstrated the potential to improve stroke outcomes by activating the PI3K/AKT signaling pathway,providing new possibilities for the treatment and rehabilitation of patients with ischemic *** investigations should focus on the direct regulatory mechanisms of drugs targeting the PI3K/AKT signaling pathway and their clinical translation to develop innovative treatment strategies for ischemic stroke.

关键词： apoptosis autophagy inflammation ischemic stroke neuroprotection oxidative stress pathogenesis phosphatidylinositol 3-kinase protein kinase B therapeutics

Effects of Nitrogen Fertilizer Treatments on Caryopsis Filling and Respiratory Rate of Rice

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Rice science 2006年第3期13卷 199-204页

作者： chen Juan WANG Zhong chen Gang Mo yi-wei Agronomy Department Agricultural College Yangzhou University Yangzhou 225009 China

An experiment was conducted to study the effects of nitrogen （N） rate and application time on grain filling and respiratory trait of caryopsis in two rice varieties, IR36 and Dali. The treatments were consisted of no N application topdressing at both tillering and booting stages （CK）, 6 g/pot of N topdressing at the tillering stage and 2 g/pot of N topdressing at the booting stage, 2 g/pot of N topdressing at the tillering stage and 6 g/pot of N topdressing at the booting stage. The results showed that the proper utilization of N fertilizer can be helpful to maintain the higher water content, higher respiratory rate and higher dehydrogenase activity of rice caryopsis in late filling phase, and prolong the course for filling and maintaining higher respiratory rate and dehydrogenase activity of rice caryopsis. More N application at booting was more effective compared to more N application at tillering.

关键词： nitrogen fertilizer water content filling duration respiratory rate dehydrogenase activity rice caryopsis

The Effects of Cyclic Stretching on the Proliferation of Lung Adenocarcinoma Cells in Vitro

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Chinese Journal of Biomedical Engineering(English Edition) 2006年第1期15卷 31-35页

作者： QU Hua WU Wen-zhou chen wei-yi College of Science Taiyuan University of Technology Taiyuan 030024 China College of Science Taiyuan University of Technology Taiyuan 030024 China College of Science Taiyuan University of Technology Taiyuan 030024 China

Using FX-4000 strain unit, the prolieration in human lung adenocarcinoma A549 cells that underwent mechanical strain of different waveform、frequency and duration were studied. Image analysis revealed that cellular proliferation rate(PR) reduced significantly after cells were subjected to square wave with 0～20% elongation at frequency 30,40,50 and 60 cycles/min for 2h. The PR had no distinct difference at heart wave , triangle wave and sine wave group compared with control. It is concluded that square wave and higher frequency play an important role in inhibiting A549 cells proliferation.

关键词： Cyclic stretch, Waveform and frequency, Lung adenocarcinoma cell , Proliferation rate

Fabrication and Mechano-sensing Characteristics of Bending Polypyrrole Actuator

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 240-245页

作者： chen Jinyou HU wei School of Automotive Engineering Hunan Financial&Industrial Vocational-technical CollegeHengyang 421002China College of Mechanical and Electrical Engineering Hunan Agricultural UniversityChangsha 410128China

To prepare a conductive polymer actuator with decent performance,a self-built experimental platform for the preparation of polypyrrole film is *** of the essential goals is to examine the mechanical characteristics of the actuator in the presence of various combinations of process parameters,combined with the orthogonal test method of"four factors and three levels".The bending and sensing characteristics of actuators of various sizes are methodically examined using a self-made bending polypyrrole *** functional relationship between the bending displacement and the output voltage signal is established by studying the characteristics of the actuator sensor subjected to various degrees of *** experimental results reveal that the bending displacement of the actuator tip almost exhibits a linear variation as a function of length and *** the voltage reaches 0.8 V,the bending speed of the actuator tends to be ***,the mechanical properties of the self-assembled polypyrrole actuator are verified by the design and fabrication of the microgripper.

关键词： conductive polymer polypyrrole mechanical characteristics actuators sensing characteristics

Dative B–N bonds weaven toward two-dimensional purely organic materials for single crystals

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Science China Chemistry 2025年第1期68卷 12-14页

作者： wei-Lei Zhou Siwei Wang Yong chen College of Chemistry and Materials Science Inner Mongolia Key Laboratory of Chemistry for Nature Products and Synthesis for Functional Molecules Innovation Team of Optical Functional Molecular Devices Inner Mongolia Minzu University College of Chemistry Nankai University

Molecular topology is one of the important topics to study and understand the relationship between molecular structure and properties [1]. Particularly, two-dimensional (2D) materials with extremely high surface area and ultra-thin morphology have attracted considerable attention due to their unexpected properties in materials and chemistry [2,3].

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