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Chinese Chemical Letters 2009年第4期20卷 397-400页

作者： Xiao Xiang zhao zhi Gang zhao Xing Li Liu Xiu Ming Wu College of Chemistry and Environmental Protection Engineering Southwest University for Nationalities Chengdu 610041 China

An efficient and simple method for the synthesis of new chiral aromatic amide molecular tweezers by irradiation with microwave under solvent-free conditions has been developed. Its main advantages are short reaction t... 详细信息

关键词： Molecular tweezer Aromatic amide Microwave irradiation Molecular recognition

Direction-of-Arrival Method Based on Randomize-Then-Optimize Approach

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Journal of Electronic Science and Technology 2022年第4期20卷 416-424页

作者： Cai-Yi Tang Sheng Peng zhi-Qin zhao Bo Jiang Science and Technology on Electronic Information Control Laboratory Chengdu 610036 School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu 611731 54th Research Institute of China Electronics Technology Group Shijiazhuang 050081

The direction-of-arrival(DOA)estimation problem can be solved by the methods based on sparse Bayesian learning(SBL).To assure the accuracy,SBL needs massive amounts of snapshots which may lead to a huge computational *** order to reduce the snapshot number and computational complexity,a randomize-then-optimize(RTO)algorithm based DOA estimation method is ***“learning”process for updating hyperparameters in SBL can be avoided by using the optimization and Metropolis-Hastings process in the RTO *** apply the RTO algorithm for a Laplace prior,a prior transformation technique is *** demonstrate the effectiveness of the proposed method,several simulations are proceeded,which verifies that the proposed method has better accuracy with 1 snapshot and shorter processing time than conventional compressive sensing(CS)based DOA methods.

关键词： Compressive sensing(CS) randomize-then-optimize(RTO) single snapshot sparse signal reconstruction

Isothermal Crystallization of iPP in Environment-friendly Diluents:Effect of Binary Diluents and Crystallization Temperature on Crystallization Kinetics

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Chinese Journal of Polymer Science 2019年第6期37卷 617-626页

作者： Yu-Jie Wang Su-Ying Yan zhi-Ping zhao Zhen-Yu Xi School of Chemistry and Chemical Engineering Beijing Institute of Technology Environmental Protection Research Institute Beijing Research Institute of Chemical IndustrySINOPEC

The growing demand for non-toxic solvents for membrane preparation has motivated the studies for green and sustainable alternatives of solvents. The effect of droplet isothermal growth within the liquid-liquid phase separation region on isothermal spherulitic growth rate of isotactic polypropylene(iPP) was investigated. The results showed that the droplets grew up at a rate of 0.0172 μm·s^(-1). The larger droplets slowed down the isothermal spherulitic growth rate of iPP. Higher mass ratio of carnauba wax(Cwax)/soybean oil(SO)resulted in faster droplet growth due to weak interaction with polymers. The isothermal crystallization behaviors of iPP in environmentfriendly binary diluents consisting of Cwax and SO mixture were further investigated experimentally using polarized optical *** was demonstrated that the isothermal spherulitic growth rate of iPP in diluents decreased nonlinearly with the increasing crystallization temperature. Compared with virgin iPP, isothermal spherulitic growth rate of iPP in SO diluent was significantly slowed down. The spherulitic growth was further retarded after the addition of Cwax in mixed diluents, resulting in a lower crystallization rate than that in SO. Moreover, the crystal form of iPP membranes was found to be α type through the characterization of small angle X-ray scattering and wide angle X-ray diffraction.

关键词： Isotactic polypropylene Carnauba wax Isothermal crystallization kinetics PP membrane

Perineural invasion of hilar cholangiocarcinoma in Chinese population: One center’s experience

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World Journal of Gastrointestinal Oncology 2020年第4期12卷 457-466页

作者： Cheng-Gang Li zhi-Peng Zhou Xiang-Long Tan zhi-Ming zhao Second Department of Hepatobiliary Surgery Chinese PLA General HospitalBeijing 100853China

BACKGROUND Hilar cholangiocarcinoma(HCCA)often produces perineural invasion(PNI)extending to extra-biliary sites,while significant confusion in the incidence of PNI in HCCA has occurred in the literature,and the mechanism of that procedure remains *** To summarize the incidence of PNI in HCCA and to provide the distribution of nerve plexuses around hepatic portal to clinical *** Reported series with PNI in HCCA since 1996 were reviewed.A clinicopathological study was conducted on sections from 75 patients with HCCA to summarize the incidence and modes of *** stains for CD34 and D2-40 in the cancer tissue were performed to clarify the association of PNI with microvessel and lymph *** of the hepatoduodenal ligament from autopsy cases were scanned and handled by computer to display the distribution of nerve plexuses around the hepatic *** The overall incidence of PNI in this study was 92%(69 of 75 patients),while the rate of PNI in HCCA in the literature ranging from 38%to 100%.The incidence of PNI did not show any remarkable differences among various differentiated groups and Bismuth-Corlette classification *** regression analysis identified the depth of tumor invasion was the only factor that correlated significantly with PNI(P<0.01).In spite of finding tumor cells that could invade microvessels and lymph ducts in HCCA,we did not find tumor cells invaded nerves via microvessels or lymph *** nerve plexuses in the hepatoduodenal ligament and Glisson’s sheath were classified,and they all surrounded the great vessels very *** The incidence of PNI of HCCA in Chinese population is around 92%and correlated significantly with a depth of tumor *** also should be considered when stratifying HCCA patients for further treatment.

关键词： Hilar cholangiocarcinoma Perineural invasion Pathology Nerve plexus Incidence Treatment

Identifying the spatiotemporal characteristics of individual red bed landslides: a case study in Western Yunnan, China

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Journal of Mountain Science 2022年第6期19卷 1748-1766页

作者： zhao Xin LI Guo zhao zhi-fang LI Chun-xiao CHEN Qi YE Xian Institute of International Rivers and Eco-Security Yunnan UniversityKunming 650050China Broadvision Engineering Consultants Co. Ltd.Kunming 650031China Yunnan Key Laboratory of Digital Communications Kunming 650000China School of Earth Sciences Yunnan UniversityKunming 650050China Research Center of Domestic High-resolution Satellite Remote Sensing Geological Engineering Kunming 650500China MNR Key Laboratory ofSanjiang Metallogeny and Resources Exploration&Utilization Kunming 650051China

Strata in red bed areas have typical characteristics of soft-hard interbedding and high sensitivity to water. Under the comprehensive action of internal stratigraphic structure and external hydrological factors, red bed landslides have highly complex spatiotemporal characteristics, presenting significant challenges to the prevention and control of landslide disasters in red bed areas, especially for slope and tunnel engineering projects. In this study, we applied an interdisciplinary approach combining small baseline subset interferometric synthetic aperture radar(SBAS-InSAR), deep displacement monitoring, and engineering geological surveying to identify the deformation mechanisms and spatiotemporal characteristics of the Abi landslide, an individual landslide that occurred in the red bed area of Western Yunnan, China. Surface deformation time series indicated that a basic deformation range developed by March 2020. Based on In SAR results and engineering geological analysis, the landslide surface could be divided into three zones: an upper sliding zone(US), a lower uplifted zone(LU), and a toe zone(Toe). LU was affected by the structure of the sliding bed with variable inclination. Using deep displacement curves combined with the geological profile, a set of sliding surfaces were identified between different lithology. The groundwater level standardization index(GLSI) and deformation normalization index(DNI) showed different quadratic relationships between US and LU. Verification using the Pearson correlation analysis shows that the correlation coefficients between model calculated results and measured data are 0.7933 and 0.7577, respectively, indicating that the DNI-GLSI models are applicable. A fast and short-lived deformation sub stage(ID-Fast) in the initial deformation stage was observed, and ID-Fast was driven by concentrated rainfall.

关键词： Red bed landslide Spatiotemporal characteristic SBAS-InSAR Deep displacement monitoring Engineering geological survey Western Yunnan

Contribution of Root Respiration to Total Soil Respiration in a Cotton Field of Northwest China

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Pedosphere 2013年第2期23卷 223-228页

作者： zhao zhi-Min zhao Cheng-Yi Y.YILIHAMU LI Ju-Yan LI Jun State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of Sciences University of Chinese Academy of Sciences

To measure the contribution of root respiration (Rr) to total soil respiration (Rt) in arid cotton fields, eighteen plots, nine for girdling and nine control, were built in an arid cotton field in the Aksu National Experimental Station of Oasis Farmland Ecosystem, Xinjiang of China. Given the difference of soil respiration between girdled plots and non-girdled control plots, the components of soil respiration, root respiration (Rr) and respiration originating from decomposition (Rd) were divided. The temperature sensitivities of R r and R d were analyzed, respectively. The results showed that the average contribution of R r to R t in arid cotton field was about 32% during the study period. The temperature-response curve of R r differed from that of Rd . The dynamic variation of R d was more related to the change of soil temperature as compared to Rr . Rr and Rd had different responses to the variation of environment, and thus new models capable of differentiating between Rr and Rd are needed for evaluating the different factors controlling these two components of soil respiration in arid cotton field.

关键词： abiotic factor decomposition girdling phenological phase temperature response value

磷石膏/木质素固化铅污染土的无侧限抗压强度

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土木与环境工程学报（中英文） 2025年第1期47卷 89-99页

作者：赵之杨秀娟石庆红樊恒辉刘翼飞西北农林科技大学水利与建筑工程学院陕西杨凌712100 西北农林科技大学岩土工程研究所/特殊岩土博物馆陕西杨凌712100

采用工业固体废弃物磷石膏、木质素对人工配制铅污染土进行固化处理,通过无侧限抗压强度(UCS)试验探究固化剂掺量、养护龄期对不同程度铅污染土固化后应力-应变曲线、破坏形态及无侧限抗压强度的影响规律,对比分析两种固化剂的固化效果... 详细信息

采用工业固体废弃物磷石膏、木质素对人工配制铅污染土进行固化处理,通过无侧限抗压强度(UCS)试验探究固化剂掺量、养护龄期对不同程度铅污染土固化后应力-应变曲线、破坏形态及无侧限抗压强度的影响规律,对比分析两种固化剂的固化效果,并采用扫描电镜(SEM)试验分析土样固化前后的微观特性。试验结果表明,磷石膏、木质素均能增大固化土的无侧限抗压强度,减小破坏应变;固化土的无侧限抗压强度随磷石膏掺量增加呈持续上升趋势,随木质素掺量增加呈先上升后下降趋势;延长养护时间能有效提高固化土无侧限抗压强度。随固化剂掺量和养护龄期的增加,土体内部胶结水平提高,土样破坏形态从局部张裂逐渐转变为剪切破坏,呈现脆性破坏特征。两种固化剂固化土效果各有优劣,木质素对高浓度铅污染土的固化效果优于磷石膏,抵抗变形能力更好,而磷石膏短期内提升强度能力及对铅的固定效果更好。扫描电镜试验表明,固化剂可起到填充孔隙、胶结土颗粒的作用,水化产物在土体内形成致密结构,宏观表现为强度增强。

关键词：磷石膏木质素铅污染土无侧限抗压强度微观特性

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Association between 5α-reductase inhibitors therapy and incidence, cancer-specific mortality,and progression of prostate cancer: evidence from a meta-analysis

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Asian Journal of Andrology 2020年第5期22卷 532-538页

作者： Lian-Min Luo Re-Dian Yang Jia-Min Wang Shan-Kun zhao Yang-Zhou Liu zhi-Guo Zhu Qian Xiang zhi-Gang zhao Department of Urology and Andrology Minimally Invasive Surgery CenterGuangdong Provincial Key Laboratory of UrologyThe First Affiliated Hospital of Guangzhou Medical UniversityGuangzhou 510230China.

5a-reductase inhibitors(5-ARI)are widely employed for the treatment of benign prostatic *** has been noted that 5-ARI exhibit the potential to attenuate the risk of prostate cancer,but consistent agreement has not been ***,the effect of 5-ARI on cancer-specific mortality and progression of prostate cancer remains ***,the goal of the current meta-analysis was to elucidate the impact of 5-ARI on the incidence and progression of prostate *** searched for all studies assessing the effect of 5-ARI on risk of prostate cancer in PubMed,Embase,Medline,and Cochrane Library *** relative risk(RR)and corresponding 95%confidence intervals(CIs)were accepted to evaluate the association between 5-ARI and the risk of prostate *** results implied that subjects who accepted 5-ARI compared with the placebo group experienced a distinctly weakened overall incidence of prostate cancer(RR=0.74;95%C l:0.66-0.82;P7;RR=1.19;95%Cl:0.98-1.43;P=0.069).The results also showed that 5-ARI treatment did not significantly alter prostate cancer-specific mortality(RR=1.0;95%C l:0.95-1.05;P=0.916).In addition,it was worth noting that 5-ARI treatment acted in a protective role that presented a dramatic benefit to delay the progression of low-risk tumors(RR=0.58;95%C l:0.43-0.78;P<0.001).

关键词： 5a-reductase inhibitor meta-analysis prostate cancer

Modification mechanism of caking and coking properties of Shenmu subbituminous coal by low-temperature rapid pyrolysis treatment

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Journal of Iron and Steel Research International 2019年第10期26卷 1052-1060页

作者： Xiang-chun Liu Bin Fang zhi-gang zhao Rui-lun Xie zhao Lei Qiang Ling Ping Cui Anhui Key Laboratory of Coal Clean Conversion&Utilization School of Chemistry and Chemical EngineeringAnhui University of TechnologyMa'anshan 243032AnhuiChina

Shenmu(SM)subbituminous coal without caking property was treated by low-temperature rapid pyrolysis(LTRP)to modify its caking and coking *** treated samples were characterized by Fourier transform infrared spectrometry,vitrinite reflectance,and X-ray diffraction to determine the modification ***,caking index(G)and coking indices(mechanical strength,coke reactivity,and coke strength after reaction)were employed to evaluate caking and coking properties,*** results showed that SM coal was gradually upgraded with increasing processing ***,the G values for the treated samples were significantly higher than that for SM coal,and G reached the maximum value at 450℃,implying the modification of caking property and the existence of an optimum temperature(450℃).Additionally,laboratory coking determinations showed that LTRP increased the mechanical strength of coke and coke strength after reaction and decreased coke reactivity when the treated coals were used in the coal blends instead of raw SM ***,LTRP treatment is effective to improve the caking and coking properties of SM coal.A mechanism was proposed for the *** upgrading degree with suitable molecular masses and some releasable hydrogen-rich donor species present within the coal,which dominate the development of caking property,is important.

关键词： Caking property Coking property Non-caking coal Low-temperature rapid pyrolysis Subbituminous coal

Design and synthesis of novel tweezer anion receptors based on deoxycholic acid

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Chinese Chemical Letters 2007年第3期18卷 287-290页

作者： Xing Li Liu zhi Gang zhao Shu Hua Chen College of Chemistry and Environmental Protection Engineering Southwest University for Nationalities Chengdu 610041 China The Faculty of Chemistry Sichuan University Chengdu 610064 China

A novel type of molecular tweezer receptors based on deoxycholic acid has been designed and synthesized and their binding properties were examined by UV-vis spectral titration. These molecular tweezers showed a high s... 详细信息

关键词： Molecular tweezers Deoxycholic acid Anion Recognition