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FeCl3-6H2O-Catalyzed Synthesis of β-Ketothioesters from Chain α-Oxo Ketene Dithioactals

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Chemical Research in Chinese Universities 2017年第5期33卷 746-752页

作者： zhao hui Jilin Province Key Laboratory of Organic Functional Molecular Design ＆ Synthesis Department of Chemistry Northeast Normal University Changchun 130024 P. R. China

A FeCl3-6H2O-catalyzed synthesis of β-ketothioesters from the hydrolysis reaction of chain α-oxoketene dithioacetals was carried out. Subsequently, we explored the FeCl3-6H2O-catalyzed Friedel-Crafts alkylation of the synthesized fl-ketothioesters with alcohols in CH3CN at 25 ℃, affording the desired α-alkylated fl-ketothioesters in excellent yields. Wide scope of the substrates, use of inexpensive reagents, high yields under mild reaction conditions are notable features of these reactions.

关键词： Iron(Ⅲ) chloride Thioester Ketene dithioacetal Hydrolysis Friedel-Crafts alkylation

Insights into in-situ imbibition behavior of fracturing fluid in propped shale fractures based on nuclear magnetic resonance:A case study from Longmaxi Formation shale,Sichuan Basin,China

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Petroleum Science 2024年第1期21卷 410-429页

作者： Jing-Jing Guo Kai-Xiang Di Lie-hui Zhang Yu-Long zhao hui-ying Tang Rui-Han Zhang Ye Tian National Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500SichuanChina

Shale gas is an important component of unconventional oil and gas *** the imbibition behavior is helpful to optimize flowback parameters and enhance gas *** imbibition studies have focused on shale matrix,and the pressure conditions discussed were mostly *** initial imbibition behavior begins from propped fractures to matrix,but there are few studies working on explaining the imbibition behavior in propped fractures or the phenomenon of many shale wells exhibit higher productivity after a“soaking”***,propped fracture samples were designed for imbibition and migration *** order to accurately study the mechanism and main influencing factors of fracturing fluid imbibition and migration in propped and unpropped shale fractures under high temperature and high pressure,a series of experiments based on nuclear magnetic resonance(NMR)were carried *** showed that NMR T_(2) spectra of all samples exhibited a bimodal *** final imbibition volume of fracturing fluid was positively related to pressure and fracture *** imbibition effect of fracturing fluid was more evident in matrix pores under high *** the migration during soaking stage,the fracturing fluid gradually migrated from large pores to small pores and gradually displaced the shale gas from the matrix,thus allowing the water blocking in propped fractures to self-unlock to some *** permeability decreased in the imbibition stage,while it recovered in the migration stage to some extent.

关键词： Forced imbibition Migration Soaking NMR T_(2)spectra Propped fracture Permeability recovery

Midterm outcome of stapled transanal rectal resection for obstructed defecation syndrome:A single-institution experience in China

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World Journal of Gastroenterology 2013年第38期19卷 6472-6478页

作者： Bin Zhang Jian-Hua Ding Yu-Juan zhao Meng Zhang Shu-hui Yin ying-ying Feng Ke zhao Department of Colorectal Surgery the Second Artillery General Hospital Department of Laboratory Medicine the Second Artillery General Hospital

AIM:To assess midterm results of stapled transanal rectal resection(STARR)for obstructed defecation syndrome(ODS)and predictive factors for ***:From May 2007 to May 2009,75 female patients underwent STARR and were included in the present *** and postoperative workup consisted of standardized interview and physical examination including proctoscopy,colonoscopy,anorectal manometry,and *** and functional results were assessed by standardized questionnaires for the assessment of constipation constipation scoring system(CSS),Longo’s ODS score,and symptom severity score(SSS),incontinence Wexner incontinence score(WS),quality of life Patient Assessment of Constipation-Quality of Life Questionnaire(PAC-QOL),and patient satisfaction visual analog scale(VAS).Data were collected prospectively at baseline,12 and 30 ***:The median follow-up was 30 mo(range,30-46 mo).Late postoperative complications occurred in 11(14.7%)*** of these patients required procedure-related reintervention(one diverticulectomy and two excision of staple granuloma).Although the recurrence rate was 10.7%,constipation scores(CSS,ODS score and SSS)significantly improved after STARR(P<0.0001).Significant reduction in ODS symptoms was matched by an improvement in the PAC-QOL and VAS(P<0.0001),and the satisfaction index was excellent in 25(33.3%)patients,good in 23(30.7%),fairly good in 14(18.7%),and poor in 13(17.3%).Nevertheless,the WS increased after STARR(P=0.0169).Incontinence was present or deteriorated in 8(10.7%)patients;6(8%)of whom were new *** analysis revealed that the occurrence of fecal incontinence(preoperative,postoperative or new-onset incontinence;P=0.028,0.000,and 0.007,respectively)was associated with the success of the ***:STARR is an acceptable procedure for the surgical correction of ***,its impact on symptomatic recurrence and postoperative incontinence may be problematic.

关键词： Colorectal surgery Constipation Stapled transanal rectal resection

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蓝碳交易认证及运行机制的挑战与应对

北京科技大学学报（社会科学版） 2025年第1期41卷 61-68页

作者：朱晖赵佳齐大连海洋大学海洋法律与人文学院大连116023

重启全国温室气体自愿减排交易市场是蓝碳纳入自愿碳市场的重要契机,但蓝碳交易制度体系仍处在初步发展阶段,缺乏完善的配套措施。我国蓝碳交易制度仍然存在交易规则功能缺失、定价机制失范、交易方式欠缺和核查监管机制不足等问题。为... 详细信息

重启全国温室气体自愿减排交易市场是蓝碳纳入自愿碳市场的重要契机,但蓝碳交易制度体系仍处在初步发展阶段,缺乏完善的配套措施。我国蓝碳交易制度仍然存在交易规则功能缺失、定价机制失范、交易方式欠缺和核查监管机制不足等问题。为保证蓝碳交易在法律规制下运行,构建公开、透明、可预期的蓝碳交易机制,应实现蓝碳交易的功能完善、规范定价机制,同时推动交易方式多元发展、健全核查机构监管机制以优化蓝碳交易运行机制,从而搭建蓝碳交易纳入自愿碳市场的规则体系。

关键词：蓝碳 CCER 交易规则定价机制监管机制

Effect of Phosphorus Fertilization to P Uptake and Dry Matter Accumulation in Soybean with Different P Efficiencies

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Journal of Integrative Agriculture 2014年第2期13卷 326-334页

作者： AO Xue GUO Xiao-hong ZHU Qian ZHANG hui-jun WANG Hai-ying MA zhao-hui HAN Xiao-ri zhao Ming-hui XIE Fu-ti College of Agronomy Shenyang Agricultural University College of Land and Environment Shenyang Agricultural University

Phosphorus （P） is an essential element for plant growth and yield. Improving phosphorus use efficiency of crops could potentially reduce the application of chemical fertilizer and alleviate environmental damage. Soybean （Glycine max （L.） Merr.） is sensitive to phosphorus （P） in the whole life history. Soybean cultivars with different P efficiencies were used to study P uptake and dry matter accumulation under different P levels. Under low P conditions, the P contents of leaf in high P efficiency cultivars were greater than those in low P efficiency cultivars at the branching stage. The P accumulation in stems of high P efficiency cultivars and in leaves of low P efficiency cultivars increased with increasing P concentration at the branching stage. At the late podding stage, the P accumulation of seeds in high and low P efficiency cultivars were 22.5 and 26.0%, respectively; and at the mature stage were 69.8 and 74.2%, respectively. In average, the P accumulation in whole plants and each organ was improved by 24.4% in high P efficiency cultivars compared to low P efficiency cultivars. The biomass between high and low P efficiency cultivars were the same under extended P condition, while a significant difference was observed at late pod filling stage. At the pod setting stage, the biomass of high P efficiency cultivars were significant greater （17.4%） than those of low P efficiency cultivars under high P condition. Meanwhile, under optimum growth conditions, there was little difference ofbiomass between the two types of cultivars, however, the P agronomic efficiency and P harvest index were significant higher in high P efficiency cultivars than those in low P efficiency cultivars.

关键词： Glycine max (L.) Merr. soybean phosphorus use efficiency

The Microstructures of Butterfly Wing Scales in Northeast of China

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Journal of Bionic Engineering 2007年第1期4卷 47-52页

作者： Li-yan Wu Zhi-wu Han zhao-mei Qiu hui-ying Guan Lu-quan Ren Key Laboratory for Terrain-Machine Bionics Engineering （Ministry of Education China） School for Biological and Agricultural Engineering Jilin University （Nanling Campus） Changchun 130022 P. R. China

There are billions of tiny scales on the butterfly wings, which array regularly as the tiles on the roof. Such tilts can form various colors of the wing and afford the species many abilities to survive and propagate. Morphological experiments on the wing scales of six butterfly species living in northeast of China were conducted. By the optics microscope; the form, geometry dimension and array of the scales were observed generally. By using scanning electron microscope （SEM）, the 2D scanning and measurement were carried out and the surface micro configurations of scales were observed. The dimension and microstructure characteristics of the cross section of single scale were achieved through transmission electron microscope （TEM）. Finally, by using 3D software, three 3D models were described and the 3D visual effect was achieved. This work can put forward a basic method for the future study on the morphology of biological microstructure.

关键词： butterfly wing scale microstructure microscope

Structures and hydrogen storage properties of RE-Mg-Ni-Mn-based AB2-type alloys prepared by casting and melt spinning

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Rare Metals 2019年第11期38卷 1086-1096页

作者： Yang-Huan Zhang Zhong-hui Hou ying Cai Feng Hu Yan Qi Dong-Liang zhao Key Laboratory of Integrated Exploitation of Baiyun Obo Multi-Metal Resources Inner Mongolia University of Science and TechnologyBaotou 014010China Department of Functional Material Research Central Iron and Steel Research InstituteBeijing 100081China

To ameliorate the electrochemical hydrogen storage properties of RE-Mg-Ni-Mn-based AB2-type electrode alloys,La element was partially substituted by Ce,and La1-xCexMgNi3.5Mn0.5(x=0,0.1,0.2,0.3,0.4)alloys were fabricated by casting and melt *** effects of Ce content on structures and electrochemical hydrogen storage properties of prepared alloys were studied in *** show that the experimental alloys consist of LaMgNi4 and LaNi5 *** variation of Ce content,instead of changing phase composition,results in an obvious phase abundance change in the alloys,namely the amount of LaMgNi4 and LaNi5 phases,respectively,increases and decreases with Ce content ***,the partial substitution of Ce for La leads to that the lattice keeps constant,cell volumes clearly decreases and the alloy grains are markedly *** electrochemical measurements reveal that the as-cast and as-spun alloys obtain the maximum discharge capacities at the first cycling without any activation *** Ce content increasing,the discharge capacity of as-cast alloys visibly *** contrast,the as-spun alloys have the maximum discharge capacity *** substitution of Ce for La dramatically promotes the cycle ***,the electrochemical kinetic performances of as-cast and asspun alloys first increase and then decrease with Ce content increasing.

关键词： AB2-type alloy Ce substitution for La Melt spinning Electrochemical properties

Construction of Ni single-atom coordinated with doped N and S elements for mild hydrogenation of methyl acrylate to methyl propionate

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Nano Research 2025年第1期18卷 217-224页

作者： Taolue Sun Chen Jian Gang Wang hui zhao Guoliang Zhang Zengxi Li Chunshan Li State Key Laboratory of Mesoscience and Engineering CAS Key Laboratory of Green Process and EngineeringBeijing Key Laboratory of Ionic Liquids Clean ProcessInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China huizhou Institute of Green Energy and Advanced Materials Huizhou 516081China Advanced Energy Science and Technology Guangdong Laboratory Huizhou 516081China

Although the nickel-based catalyst is able toexhibit comparative catalytic activity to noble metal formethyl acrylate hydrogenation,it requires strict reactioncondition,which can be improved by regulation ofcoordination *** this study,we constructed akind of Ni single-atom coordinated with N and S(Ni-NSC)through the pyrolysis of organic Ni-based precursors at600℃.The existence and fine structure of Ni single-atom were confirmed by the spherical electron microscopicobservation in combination with the X-ray absorption spectroscopy(XAS)*** addition,the catalytichydrogenation assessment suggested that the as-prepared Ni-NSC catalyst exhibited higher activity and stability than theNi/NSC supported catalyst prepared by incipient wetness impregnation *** remarkable catalytic activity was dueto the high dispersion and density of Ni single-atom and weak adsorption energy of intermediates on these Ni sites.

关键词： methyl acrylate mild hydrogenation Ni single-atom coordination environment adsorption energy

The quasitriangular structures of biproduct Hopf algebras

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第1期8卷 149-157页

作者： zhao Li-hui zhao Wen-zheng Department of Mathematics Zhejiang University Hangzhou 310027 China Department of Mathematics Henan Normal University Xinxiang 453002 China

The construction of the biproduct of Hopf algebras, which consists of smash product and the dual notion of smash coproduct, was first formulated by Radford. In this paper we study the quasitriangular structures over biproduct Hopf algebras B*H. We show the necessary and sufficient conditions for biproduct Hopf algebras to be quasitriangular. For the case when they are, we determine completely the unique formula of the quasitriangular structures. And so we find a way to construct solutions of the Yang-Baxter equation over biproduct Hopf algebras in the sense of (Majid, 1990).

关键词： Hopf algebra Quasitriangular structure Biproduct