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Science China Chemistry 2018年第3期61卷 294-299页

作者： Mingxuan Liu Yiming Li lei Yu Qing Xu Xuefeng Jiang Institute of Pesticide School of Chemistry and Chemical Engineering and School of Horticulture and Plant Protection Yangzhou University Shanghai Key Laboratory of Green Chemistry and Chemical Process Department of Chemistry East China Normal University

Under iodine-catalyzed and visible light-irradiated aerobic conditions, selenoalkoxylation of olefins with diselenides and alcohols can be efficiently achieved to afford the useful α-alkoxyl selenides in the presence of only 0.5 equiv. of H_2O_2. Controlling the sub-stoichiometric H_2O_2 amount is crucial to avoid the non-selective over-oxidation of the diselenides that leads to the ineffective hyper-valent selenium compounds. Meanwhile, under visible light irradiation, the green, safe, and low-cost air can work as a supplemental mild oxidant in the reaction to ensure selective oxidation of the diselenides, full conversion of the reactants, and ultimately good yield of the products.

关键词： selenium alkoxyl selenide aerobic oxidation visible light iodine catalysis

Coiflet solution of strongly nonlinear p-Laplacian equations

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Applied Mathematics and Mechanics(English Edition) 2017年第7期38卷 1031-1042页

作者： Cong XU Jizeng WANG Xiaojing LIU lei ZHANG Youhe ZHOU Key Laboratory of Mechanics on Disaster and Environment in Western China the Ministry of Education College of Civil Engineering and Mechanics Lanzhou University Lanzhou 730000 China

A new boundary extension technique based on the Lagrange interpolat- ing polynomial is proposed and used to solve the function approximation defined on an interval by a series of scaling Coiflet functions, where the coefficients are used as the single-point samplings. The obtained approximation formula can exactly represent any polynomials defined on the interval with the order up to one third of the length of the compact support of the adopted Coiflet function. Based on the Galerkin method, a Coifiet-based solution procedure is established for general two-dimensional p^Laplacian equations, following which the equations can be discretized into a concise matrix form. As examples of applications, the proposed modified wavelet Galerkin method is applied to three typical p-Laplacian equations with strong nonlinearity. The numerical results justify the efficiency and accuracy of the method.

关键词： wavelet Galerkin method Coiflet boundary extension p-Laplacian equa-tion

Therapeutic potential of urine-derived stem cells in renal regeneration following acute kidney injury:A comparative analysis with mesenchymal stem cells

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World Journal of Stem Cells 2024年第5期16卷 525-537页

作者： Fang Li Bin Zhao lei Zhang Guo-Qing Chen Li Zhu Xiao-Ling Feng Meng-Jia Gong cheng-Chen Hu Yuan-Yuan Zhang Ming Li Yong-Qiang Liu Department of General Surgery Chongqing General HospitalChongqing 401147China Department of Pediatric Research Institute Children’s Hospital of Chongqing Medical UniversityChongqing 401147China

BACKGROUND Acute kidney injury(AKI)is a common clinical syndrome with high morbidity and mortality *** use of pluripotent stem cells holds great promise for the treatment of ***-derived stem cells(USCs)are a novel and versatile cell source in cell-based therapy and regenerative medicine that provide advantages of a noninvasive,simple,and low-cost approach and are induced with high multidifferentiation *** these cells could serve as a potential stem cell source for the treatment of AKI has not been *** Stem cell markers with multidifferentiation potential were isolated from human amniotic *** severe combined immune deficiency(SCID)mice models were induced by means of an intramuscular injection with *** isolated from human-voided urine were administered via tail *** functional changes in the kidney were assessed by the levels of blood urea nitrogen and serum *** histologic changes were evaluated by hematoxylin and eosin staining and transferase dUTP nick-end labeling ***,we compared the regenerative potential of USCs with bone marrow-derived mesenchymal stem cells(MSCs).RESULTS Treatment with USCs significantly alleviated histological destruction and functional *** renal function was rapidly restored after intravenous injection of 5×105 human USCs into SCID mice with glycerol-induced AKI compared with injection of *** from secretion assays conducted in vitro demonstrated that both stem cell varieties released a wide array of cytokines and growth *** suggests that a mixture of various mediators closely interacts with their biochemical *** types of stem cells showed enhanced tubular cell prolif-eration and decreased tubular cell apoptosis,although USC treatment was not more effective than MSC *** found that USC therapy significantly improved renal function and histological damage,inhibited inflammation and apoptosis processes in the kid

关键词： Urine-derived stem cells Regenerative medicine Acute kidney injury Renal function recovery Cell therapy

Anesthesia and perioperative management for giant adrenal Ewing’s sarcoma with inferior vena cava and right atrium tumor thrombus:A case report

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World Journal of Clinical Cases 2022年第2期10卷 643-655页

作者： Ji-Lian Wang Chuan-Ya Xu Chun-Jing Geng lei Liu Ming-Zhu Zhang Hua Wang Ruo-Tao Xiao Lu Liu Geng Zhang cheng Ni Xiang-Yang Guo Department of Anesthesiology Peking University Third HospitalBeijing 100191China Department of Urology Peking University Third HospitalBeijing 100191China Department of Anesthesiology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China Department of Pathology School of Basic Medical SciencesPeking University Health Science CenterBeijing 100191China Intensive Care Unit Peking University Third HospitalBeijing 100191China

BACKGROUND Ewing’s sarcoma of the adrenal gland with inferior vena cava(IVC)and right atrium thrombus is extremely ***,we report a case of giant adrenal Ewing’s sarcoma with IVC and right atrium tumor thrombus and summarize the anesthesia and perioperative *** SUMMARY A young female was admitted to the Department of Urology with intermittent pain under the right costal arch for four *** abdominal computed tomography revealed a large retroperitoneal mass(22 cm in diameter),which may have originated from the right adrenal gland and was closely related to the *** echocardiography showed a strong echogenic filling measuring 70 mm extended from the IVC into the right atrium and *** preoperative preparation with cardiopulmonary bypass,sufficient blood products,transesophageal echocardiography and multiple monitoring,tumor and thrombus resection by IVC exploration and right atriotomy were successfully performed by a multidisciplinary *** hemodynamic stability was the major concern of anesthesiologists and the status of tumor thrombus and pulmonary embolism were monitored *** transfer of the patient to the intensive care unit(ICU),cardiac arrest occurred without external *** resuscitation was performed immediately and cardiac function was restored after 1 *** the ICU,extracorporeal membrane oxygenation(ECMO)and continuous renal replacement therapy(CRRT)were provided to maintain cardiac,liver and kidney *** examination confirmed the diagnosis of Ewing’s *** postoperative treatments and rehabilitation,the patient was discharged from the urology *** An adrenal Ewing’s sarcoma with IVC and right atrium thrombus is extremely rare,and its anesthesia and perioperative management have not been ***,this report provides significant insights in the perioperative management of patients with adrenal Ewing’s sarcoma and IVC

关键词： Ewing’s sarcoma Anesthesia Inferior vena cava Cardiac arrest Tumor thrombus

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一种基于丢失距离的无人机网络效能优化方法

无线互联科技 2020年第18期17卷 13-14,27页

作者：叶磊程龙南部战区海军参谋部某中心广东湛江524000 91878部队广东湛江524000

目前,无人机得到广泛应用,但其拓扑变化快速,存在传输距离、信号衰减、干扰等因素,传输效能相较于传统网络大幅降低。文章在传输层上引入丢失距离概念,控制发送窗口,在环境恶劣时控制发送速率,提高通信效率降低能耗,通过分析与仿真验证... 详细信息

目前,无人机得到广泛应用,但其拓扑变化快速,存在传输距离、信号衰减、干扰等因素,传输效能相较于传统网络大幅降低。文章在传输层上引入丢失距离概念,控制发送窗口,在环境恶劣时控制发送速率,提高通信效率降低能耗,通过分析与仿真验证了该算法能够发挥一定效果。

关键词：无人机网络丢失距离发送窗口通信效能

A comparison study on viscosity and heat transfer property of fluorinebearing and fluorine-free mold flux for casting silicon steel

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Journal of Iron and Steel Research International 2019年第4期26卷 385-392页

作者： De-xiang Cai Wan-lin Wang lei Zhang Chen Zhang School of Metallurgy and Environment Central South UniversityChangsha 410083HunanChina Steelmaking Research Department Baosteel Group Corporation Research InstituteShanghai 201900China

A comparison study was conducted on viscosity and heat transfer property of the traditional fluorine-bearing(F-bearing)mold flux and the newly designed fluorine-free(F-free)mold flux for casting silicon *** results showed that the viscosity of F-free mold flux is lower than that of F-bearing mold flux,as the apparent activation energy of F-free mold flux is also lower than that of F-bearing mold flux confirmed by the kinetics results for viscous flow,which meant that the energy barrier of F-free mold flux that the migration of ion clusters needs to overcome is smaller,and thus leads to a lower viscosity of F-free mold ***,the research results of the heat transfer suggested that the comprehensive heat transfer coefficient of F-free mold flux is lower than that of F-bearing mold flux in all *** reason is that the true density of F-free mold flux increases from glassy state to crystalline state,while that of F-bearing mold flux is *** reason is that the air gap gets increased due to the volume shrinkage of F-free mold flux from glassy state to crystalline state and the solidification of the molten *** introduce a larger thermal resistance of F-free mold flux than that of F-bearing mold *** the comparison,the designed F-free mold flux shows a better lubrication and capacity to control the heat transfer than the traditional F-bearing mold flux.

关键词： Silicon steel Mold flux Viscosity True density Heat transfer

A comparative investigation of NdSrCu_(1-x) Co_x O_(4-δ) and Sm_(1.8) Ce_(0.2) Cu_(1-x) Co_x O_(4-δ) (x:0–0.4) for NO decomposition

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Journal of Environmental Sciences 2010年第3期22卷 448-453页

作者： Jiguang Deng lei Zhang Yunsheng Xia Hongxing Dai Hong He Laboratory of Catalysis Chemistry and Nanoscience Department of Chemistry and Chemical Engineering College of Environmental and Energy EngineeringBeijing Unversity of Technology Beijing 100124 China.

A series of single-phase T-structured NdSrCu 1-x Co x O 4-δ with oxygen vacancies and T -structured Sm 1.8 Ce 0.2 Cu 1-x Co x O 4-δ （x： 0–0.4） with oxygen excess were prepared using ultrasound-assisted citric acid complexing method, and characterized by means of techniques such as thermogravimetric analysis and NO temperature-programmed desorption （NO-TPD）. The catalytic activities of these materials were evaluated for the decomposition of NO. It was found that the NdSrCu 1-x Co x O 4-δ catalysts were of oxygen vacancies whereas the Sm 1.8 Ce 0.2 Cu 1？x Co x O 4-δ ones possessed excessive oxygen （i.e., over-stoichiometric oxygen）; with a rise in Co doping level, the oxygen vacancy density of NdSrCu 1-x Co x O 4-δ decreased while the over-stoichiometric oxygen amount of Sm 1.8 Ce 0.2 Cu 1-x Co x O 4-δ increased. The NO-TPD results revealed that NO could be activated much easier over the oxygen-deficient perovskite-like oxides than over the oxygen-excessive perovskite-like oxides, with the NdSrCuO 3.702 catalyst showing the best efficiency in activating NO molecules. Under the conditions of 1.0% NO/helium, 2800 hr -1 , and 600–900°C, the catalytic activity of NO decomposition followed the order of NdSrCuO 3.702 〉 NdSrCu 0.8 Co 0.2 O 3.736 〉 NdSrCu 0.6 Co 0.4 O 3.789 〉 Sm 1.8 Ce 0.2 Cu 0.6 Co 0.4 O 4.187 〉 Sm 1.8 Ce 0.2 Cu 0.8 Co 0.2 O 4.104 〉 Sm 1.8 Ce 0.2 CuO 4.045 , in concord with the sequence of decreasing oxygen vacancy or oxygen excess density. Based on the results, we concluded that the higher oxygen vacancy density and the stronger Cu 3＋ /Cu 2＋ redox ability of NdSrCu 1-x Co x O 4-δ account for the easier activation of NO and consequently improve the catalytic activity of NO decomposition over the catalysts.

关键词： perovskite-like oxide catalysts NO decomposition oxygen nonstoichiometry Cu^ 3+ /Cu ^2+ Cu^ 2+ /Cu^ +

Transport and selectivity of indium through polymer inclusion membrane in hydrochloric acid medium

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Frontiers of Environmental Science & Engineering 2017年第6期11卷 79-88页

作者： Xiaorong Meng Conghui Wang Pan Zhou Xiaoqiang Xin lei Wang School of Science Xi'an University of Architecture and Technology Xi'an 710055 China School of Environmental & Municipal Engineering Xi'an University of Architecture and Technology Xi'an 710055 China Key Laboratory of Membrane Separation of Shaanxi Province Xi'an 710055 China

In the present paper, a polymer inclusion membrane （PIM） containing polyvinyl chloride （PVC）, and bis-（2-ethylhexyl） phosphate （D2EHPA） which was used as extracting agent was used for the recovery of In（Ⅲ） ions in hydrochloric acid medium. The effects of carrier concentration, feed phase pH, strip phase HCI concentration, temperature on the transport, and the membrane＇s stability and thickness were examined. And the conditions for the selective separation of In（Ⅲ） and CU（Ⅱ） were optimized. The results showed that the transport of In（Ⅲ） across PIM was consistent with the first order kinetics equation, and also it was controlled by both the diffusion of the metal complex in the membrane and the chemical reaction at the interface of the boundary layers. The transport flux （J0） was inversely proportional to the membrane thickness, however, the transport stability improved as the membrane thickness increased. The transport flux of In（Ⅲ） and CU（Ⅱ） was decreased by excessive acidity of feed phase and high concentration of Cl^- . The selectivity separation coefficient of In（Ⅲ）/Cu（Ⅱ） was up to 34.33 when the original concentration of both In（Ⅲ） and Cu（Ⅱ） was 80 mg· L^ -1 as well as the pH of the feed phase and the concentration of Cl^- in the adjusting context were 0.6 and 0.5 mol· L^-1, respectively. Within the range of pH = 1-3, the separation selectivity of In（Ⅲ）/Cu（Ⅱ） reached the peak in the case when the Cl^- concentration was 0.7 mol·L^ -1.

关键词： Polymer inclusion membrane Selective transport D2EHPA In(Ⅲ) Cu(Ⅱ)

An Adaptive SVD Method for Solving the Pass-Region Problem in S-Transform Time-Frequency Filters

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Chinese Journal of Electronics 2015年第1期24卷 115-123页

作者： YIN Baiqiang HE Yigang LI Bing ZUO lei YUAN Lifen School of Electrical and Automation Engineering Hefei University of Technology

S-transform(ST) is an excellent tool for time-frequency filter. There are two factors that influence filtering performance: Inverse s-transform(IST) algorithms and the pass-regions in time-frequency domain. A novel matrix IST algorithm is derived and an adaptive Singular value decomposition(SVD) method for solving the pass-region problem is proposed. The former can avoid reconstructing errors in time-frequency filtering; the latter is effective to distinguish the pass-region of signal from *** can be realized by removing the smaller singular values and keeping the larger singular values. An additive noise perturbation model is built in ST time-frequency domain and the effective rank of noise perturbation model based on matrix IST is analyzed. Simulation results indicate that the proposed SVD method can provide higher precision than the existing ones at low signal-to-noise ratio and does not need to compute the noise statistics *** examples verify the effectiveness of proposed method.

关键词： S-transform Matrix inverse S-transform Time frequency filter Singular value decomposition.

Response of a pile group behind quay wall to liquefaction-induced lateral spreading:a shake-table investigation

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Earthquake Engineering and Engineering Vibration 2014年第4期13卷 741-749页

作者： Tang Liang Zhang Xiaoyu Ling Xianzhang Su lei Liu Chunhui School of Civil Engineering Harbin Institute of Technology Key lab of Structures Dynamic Behavior and Control of the Ministry of Education Harbin Institute of Technology

The response of pile foundations near a quay wall under liquefaction-induced lateral spreading remains a complex problem. This study presents the results of a shake-table test on a 2×2 pile group behind a sheet-pile quay wall that was subjected to lateral spreading. The quay wall was employed to trigger liquefaction-induced large lateral ground deformation. The discussions focus on the behavior of the pile and the soil and on the bending moment distributions within the group pile and the restoring force characteristics at the superstructure. Overall, the piles exhibited apparent pinning effects that reduced soil deformation. In addition, the rear-row piles near the quay wall experienced larger bending moments than did the front-row piles, indicating significant pile group effects. The tests showed that lateral spreading could be a primary cause of larger monotonic deformations and bending moments. It can also be concluded that the monotonic bending moments were significantly decreased due to the presence of slow soil flow. The stiffness at the superstructure was reduced because of accumulated excess pore pressure before liquefaction, and it was recovered during lateral spreading. The present study further enhances current understanding of the behavior of low-cap pile foundations under lateral spreading.

关键词： lateral spreading liquefaction pile group behavior shake-table experiment