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A new series of chiral catalysts for the enantioselective borane reduction of ketones

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Chinese journal of Chemistry 1997年第5期15卷 459-463页

作者： Shen, ZX Zhang, YW Lu, j Xu, XN Lu, cr Suzhou Univ Sch Chem & Chem Engn Suzhou 215006 Jiangsu Peoples R China

A new series of 1,3,2-oxazaborolidine catalysts substituted in position 4 by the (CH3)(3)C(CH2)(n) group (n=2, 3, 4, 5) were synthesized and applied to the borane reduction of prochiral ketones. The relationship betwe... 详细信息

关键词： oxazaborolidine enantioselective borane reduction enantioselectivity

Full-spectrum Bi@SrTiO_(3) for bi-directional promotion effects on photocatalytic redox reaction:Insight into intermediates and mechanism

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journal of Rare Earths 2024年第5期42卷 917-929,I0004页

作者： Bin Liu Nanhao Zhou jun Liu Xinglei Wang Peter K.j.Robertson Xiaoyuan Chen Chao Chen jianmin Luo Chuanyi Wang School of Chemistry and Civil Engineering Shaoguan UniversityShaoguan512005China Chengdu Customs Technology Center Chengdu610041China Key Laboratory of Pollutant Chemistry and Environmental Treatment College of Chemistry and Environmental ScienceYili Normal UniversityYining835000China School of Chemistry and Chemical Engineering Queen's University BelfastStranmillis RoadBelfastBT95AGUnited Kingdom Guangzhou Institute of Industrial Intelligence(GIII) Guangzhou511400China

The development of full-spectrum photocatalysts active in the near-infrared(NIR)region has gained increasing attention for deleterious pollutant *** integration of plasmonic metals with semico nductors is an effective way to widen the light re sponse range of photocatalysts due to the strong light absorption and fast plasmonic energy transfer of the localized surface plasmon resonance(LSPR).In this work,the full-spectrum responsive Bi@SrTiO_(3) was prepared via facile solvothermal chemical *** optimal Bi@SrTiO_(3) achieves exceptional photocatalytic cr(VI)reduction efficiency and tetracycline degradation,realizing bi-directional promotion effects on redox *** to density functional theory(DFT)simulations,the extraordinary photocatalytic performance is attributed to the tunable builtin electric field(IEF)of the Ohmic *** favorable adaptability in real water and high stability of BSTO-25 were proved by experime ntal *** the po ssible photocatalytic mechanism was proposed based on theoretical calculation and experimental ***,the non-toxicity of the BSTO-25 was evaluated by *** cultivation,which further proves the feasibility of treating wastewater with *** work provides a new perspective on constructing full-spectrum-driven photocatalysts for applications dealing with environmental remediation.

关键词： Full-spectrum photocatalysts Localized surface plasmon resonance Ohmic contact cr(Ⅵ)reduction Antibiotic degradation Rare earths

Uncovering the hierarchical clusters in the heat-affected zone of an electron beam weldedα/βtitanium alloy joint

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journal of Materials Science & Technology 2024年第7期174卷 120-132页

作者： C.Xu X.H.Shao H.j.Yang M.Lv H.Q.Liu X.L.Ma Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Suzhou laboratory Suzhou 215028China Department of Mechanical Engineering Kyushu UniversityFukuoka 819-0395Japan Bay Area Center for Electron Microscopy Songshan Lake Materials LaboratoryDongguan 523808China

Using high-resolution transmission Kikuchi diffraction(TKD)and transmission electron microscopy(TEM),we examined the hierarchical clusters that form in situ in the heat-affected zone(HAZ),which are com-monly referred to as“ghost”structures,of bimodal titanium alloy Ti-5Al-2Sn-2Zr-4Mo-4cr(wt%,TC17).The ghost structures are enriched with Al elements but poor in Mo and cr compared to the surroundingβ*** results show that the ghost structure in middle-HAZ mainly consists ofα_(L)laths with a high-angle grain boundary,which exhibits the classic Burgers orientation relationship(BOR)with the host matrix,while it encircles theα_(P)grains in *** the ghost structure is evidenced to form via in-complete martensitic *** results further confirm that the ghost structure is composed ofαL and tinyβ_(L)laths with BOR,with the former being enriched with Al and poor with cr and Mo,while the latter is the ***,twoα_(L)variant clusters with a check-mark morphology are fre-quently observed viewed along[0001]_(αL)//[110]_(βL)directions,which are dominated by the crystallographic and geometrical relationships betweenαandβ*** on the microstructural characterization,it is hypothesized that the ghost structure is transformed from the initialα_(P)phase,due to the coupling ef-fect of high thermal stress(which induces the formation of a large number of dislocations)and element diffusion caused by sudden temperature increase and plunge cooling in the HAZ during the welding pro-cess.

关键词： TC17 titanium alloy Electron beam welding(EBW) The ghost structure Transmission Kikuchi diffraction(TKD) Transmission electron microscopy(TEM)

Strategy of preparing SmCo based films with high coercivity and remanence ratio achieved by temperature and chemical optimization

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journal of Rare Earths 2024年第7期42卷 1289-1297,I0004页

作者： Yansong Gong Zhaoguo Qiu Sizhe Liang Xinrui Zheng Hongxia Meng Zhigang Zheng Deyang Chen Shengfu Yuan Weixing Xia Dechang Zeng j.P.Liu School of Materials Science and Engineering South China University of TechnologyGuangzhou510640China Zhongshan R&D Center for Materials Surface and Thin Films Technology of the South China University of Technology Gent Materials Surface Technology(Guangdong)Co.Ltd.Zhongshan528437China Institute for Advanced Materials South China Academy of Advanced OptoelectronicsSouth China Normal UniversityGuangzhou510006China Yangjiang Branch Guangdong Laboratory Materials Science and Technology Yangjiang Advanced Alloys LaboratoryYangjiang529500China Laboratory of Rare-Earth Magnetic Functional Materials Ningbo Institute of Material Technology and EngineeringChinese Academy of SciencesNingbo315201China Department of Physics University of Texas at ArlingtonArlingtonTX76019USA

SmCo based films with excellent intrinsic magnetic properties have promising applications in micro-electro-mechanical system(MEMS).However,due to the complexity of phase composition and uncontrollable crystallization degree of SmCo hard magnetic phase in the film,both the coercivity(Hc)and remanence(Mr)of films are difficult to enhance *** this paper,SmCo based films were deposited with a cr underlayer and capping layer on single crystal Si substrates via magnetron sputtering *** effects of annealing parameters and Sm/Co atomic ratio on the phase structure and coercivity of films are *** adjusting the Sm/Co atomic ratio from 1:5 to 1:4,Co soft magnetic phase disappears and the single phase SmCo5 is obtained,leading to the increase of coercivity of the films from 30 to 34 *** influence of deposition temperature and Cu doping on magnetic properties of SmCo based films was *** the deposition temperature increases from room temperature to 250℃,the coercivity will further increase from 34 to 51 ***,a severe kink is observed in the demagnetization curves due to the poor exchanged *** analysis of transmission electron microscopy(TEM)confirms that the average size of non-hard magnetic amorphous phase exceeds the effective exchanged coupling length of SmCo5,which contributes to the decoupling and low remanence ***,doping Cu and applying a post-annealing process can significantly improve the crystallization degree of the *** the coercivity and the remanence ratio of the demagnetization curves are greatly *** propose a plausible strategy to prepare the SmCo based films with high coercivity and remanence ratio by temperature and chemical optimization,which can be utilized in high performed MEMS devices.

关键词： Rare earths SmCo based films Phase composition crystallization conditions Coercivity Remanence ratio

Endoscopic full-thickness resection of gastric stromal tumor arising from the muscularis propria

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Chinese Medical journal 2013年第13期126卷 2435-2439页

作者： Zhang B Huang LY Wu cr Cui j jiang LX Zheng HT Department of GastroenterologyYantai Yuhuangding Hospital affiliated to Medical College of Qingdao University Yantai Shandong 264000 China Department of Abdominal SurgeryYantai Yuhuangding Hospital affiliated to Medical College of Qingdao University Yantai Shandong 264000 China

Background Gastric stromal tumors are the most common type of tumor originating from mesenchymal tissue. The traditional method for the treatment of gastric stromal tumor is surgical operation or therapeutic laparoscopy. More recently, endoscopic micro-traumatic surgery has become possible for gastric stromal tumors, with any perforation caused by endoscopic therapy mended endoscopically. We assessed the effectiveness of endoscopic full-thickness resection （EFR） in the treatment of gastric stromal tumors arising from the muscularis propria. Methods Of the 42 gastric stromal tumors, each 〉2.0 cm in diameter, arising from the muscularis propria, 22 were removed by EFR and 20 by laparoscopic surgery. Tumor expression of CD34, CDl17, Dog-l, S-100, and smooth muscle actin （SMA） was assessed immunohistochemically. Operating time, complete resection rate, length of hospital stay, incidence of complications, and recurrence rates were compared between the two groups. Continuous data were compared by using independent samples t-tests and categorical data by using Xz tests. Results Comparisons of the 22 gastric stromal tumors treated with EFR and the 20 treated with laparoscopic surgery showed similar operation times （60-155 minutes （mean, （90±17） minutes） vs. 50-210 minutes （mean, （95±21） minutes）, P 〉0.05）, complete resection rates （100% vs. 95%, P 〉0.05）, and length of hospital stay （4-10 days （mean, （6.0±1.8） days） vs. 4-12 days （mean, （7.3±1.7） days）, P 〉0.05）. None of the patients treated with EFR experienced complications, whereas one patient treated with laparoscopy required a conversion to laparotomy and one experienced postoperative gastroparesis. No recurrences were observed in either group. stromal tumors diagnosed by gastroscopy and endoscopic remaining 36 were stromal tumors. mmunohistochemical staining showed that of the 42 gastric ultrasound, six were leiomyomas （SMA-positive） and the Conclusions Gastric stromal tumors arising from the muscularis propria can be

关键词： gastrointestinal stromal tumor " treatment " endoscopy " muscularis propria " resection

Removal of As(V)in the presence of cr(VI)in contaminated water from the Bajio region of Mexico using ferrihydrite-functionalized graphene oxide(GOFH):A case study

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Emerging Contaminants 2024年第3期10卷 134-144页

作者： D.R.joya-Cardenas j.P.Rodríguez-Caicedo M.A.Corona-Rivera N.Saldana-Robles C.E.Damian-Ascencio A.Saldana-Robles Graduate Program in Biosciences University of GuanajuatoIrapuato36500Mexico Facultad de Ingenierías y Tecnologías Instituto XeriraUniversidad de SantanderBucaramanga680003Colombia Chemical Engineering Unit Academic Multidisciplinary Region Altiplano UAMRA.Autonomous University of San Luis PotosíMatehualaSan Luis Potosí78000Mexico Department of Agricultural Engineering University of GuanajuatoIrapuato36500Mexico Department of Mechanical Engineering University of GuanajuatoSalamanca36800Mexico Mechanical Engineering Department Virginia TechBlacksburgVA24061USA

The presence of heavy metals such as arsenic(As)and chromium(cr)can be considered one of the most toxic heavy *** study aims to develop and evaluate a graphene oxide(GO)based material functionalized with ferrihydrite for the removal of As(V)in the presence of cr(VI).The adsorbent ferrihydrite-functionalized graphene oxide(GOFH)was characterized by SEM,FTIR,XRD,XPS,surface charge,BET and *** adsorption capacities for As(V)and cr(VI)were 160 and 66 mg g^(-1)respectively at pH 4 and 298 K,fitting the Langmuir *** binary systems,GOFH adsorbed As(V)with an adsorption capacity of 137 mg g^(-1)in the presence of 20 mg L^(-1)cr(VI)at room *** analysis revealed an exothermic and spontaneous ***,GOFH effectively removed several coexisting anions from groundwater,including SO_(4)^(2-),CO_(3)^(2-)and Cl^(-).This work evidences the potential of GOFH for competitive adsorption of priority pollutants from complex *** GOFH material represents a technically and economically viable technology for application in groundwater decontamination,as it requires inexpensive precursors and ambient conditions during synthesis and operation.

关键词： Competition Ions Contamination Groundwater Adsorption capacity

Population Fluctuation and Vertical Distribution of the Soybean Looper (<i>Chrysodeixis includes</i>) in Soybean Culture

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American journal of Plant Sciences 2018年第7期9卷 1544-1556页

作者： Daniele Zulin crébio j. ávila Eunice C. Schlick-Souza Postgraduate Program in Entomology and Biodiversity Conservation Universidade Federal da Grande Dourados Doura-dos-MS Brazil Embrapa Agropecuária Oeste Dourados-MS Brazil Instituto Federal de Mato Grosso Campo Novo do Parecis-MT Brazil

The objective of this work was to study the population fluctuation and the vertical distribution of the Chrysodeixis includes (Walker) (Lepidoptera: Noctuidae) in the leaf canopy of soybeans. The experiments were conducted under field conditions in the experimental area of the Embrapa Agropecuária Oeste during the 2014/2015 harvest. Adult monitoring was performed using Delta-type traps, baited with the pest sexual pheromone. The eggs were collected in the soybean plants and the caterpillars monitored through the beat cloth. The population peaks of C. includes occurred in the reproductive period of the soybean plants, although the adults were also found in the season soybean. Although there was no significant relationship between the trapped adults and the immature forms of C. includes sampled with the beat cloth, a significant linear and positive relationship was found between the egg and caterpillar densities of the pest in the culture. Adults preferentially oviposited on the lower part of the soybean plants, while the caterpillars preferred to position themselves predominantly in the lower and mid region of the plants. However, at warmer temperatures during the day, the caterpillars migrate to the upper areas of the soybean plants.

关键词： Glycine Max Monitoring Sexual Pheromone Behavior

COST ESTIMATE FOR SMALL BOX CIRDER AND DRUM DECK BRIDGES IN REINFORCED AND PRESTRESSED CONcrETE

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COST ESTIMATE FOR SMALL BOX CIRDER AND DRUM DECK BRIDGES IN ...

The International Symposium on Modern Applications of Prestressed Concrete

作者： E.P.j.van Vuuren S.F.cr（?）ter Professor of Civil Engineering Rand Afrikaans University jOHANNESBURG Republic of South Africa Engineer BKS Incorporated PRETORIA Republic of South Africa

＜正＞It is difficult to estimate the cost of bridge structures at the route planning stage as only very preliminary information is available at the time. This paper describes a method to estimate the costs with suffi...

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光交换的崛起

科学（中文版） 2001年第4期 58-63页

作者： Bishop,David j Giles,cr 等朗讯贝尔实验室的微机械研究室贝实验室微机械研究室