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The first catalytic asymmetric addition of diethylzinc to aldehyde promoted by chiral thiourea

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Chinese Chemical Letters 2011年第11期22卷 1265-1268页

作者： zhi Guo Qiao Tian Hua Shen Zhen Fang Fu Jun Qi Li Hong Wang qing Bao Song The State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology College of Chemical Engineering and Materials Science Zhejiang University of Technology Hangzhou 310032 China

A series of C_2-symmetric and asymmetric chiral thiourea derivatives were synthesized from commercial *** of the new compounds have been fully characterized by IR,~1H NMR,^（13）C NMR,MS spectra and elemental *** chiral thioureas were used as chiral ligands in the catalytic enantioselective ethylation of aldehydes with diethylzinc,the corresponding sec-alcohols were gained with excellent enantioselectivities（up to 87.1%ee） and high yields（up to 76.7%） after the conditions were optimized.

关键词： Chiral thiourea Diethylzinc Amino alcohol C_2-symmetric Enantioselective addition

清末粤东新式学堂创设:丘逢甲与日本东亚同文会会员

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韩山师范学院学报 2024年第2期45卷 18-25页

作者：曾志灵广东技术师范大学外国语学院广东广州510665

清末丘逢甲借力日本东亚同文会,创设岭东同文学堂。丘逢甲的初衷是岭东同文学堂设于汕头埠,由于同仁杨鲁等人皆认为应设在潮州,于是在潮州开设了东文学堂。但丘逢甲仍与林梁任“继续推动在汕头兴学的原议”创设岭东同文学堂。清末粤东... 详细信息

清末丘逢甲借力日本东亚同文会,创设岭东同文学堂。丘逢甲的初衷是岭东同文学堂设于汕头埠,由于同仁杨鲁等人皆认为应设在潮州,于是在潮州开设了东文学堂。但丘逢甲仍与林梁任“继续推动在汕头兴学的原议”创设岭东同文学堂。清末粤东新式学堂,除了潮州的东文学堂,还有汕头埠的岭东同文学堂,并没有学界所讨论的汕头东(同)文学堂。且两家学堂在1901年6月前均有实际办学,聘请了东亚同文会会员为日本教习。至于日本东亚同文会的报告,为何出现“汕头东文学堂”和“汕头同文学堂”等名称,有两种可能,一是日本东亚同文会广东支部夸大成绩,二是潮州话的“同”与“东”同音,报告撰写者的随意性使用。

关键词：岭东同文学堂丘逢甲东亚同文会清末新式学堂日本教习

Identification and effective regulation of scarb1 gene involved in pigmentation change in autotetraploid Carassius auratus

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1985—2019年中国苔藓产业专利布局与趋势分析

动物学研究 2024年第2期 381页

作者： Xi-Dan xu Yue Zhou Chong-qing Wang xu Huang Kun Zhang Xiao-Wei xu Li-Wen He Xin-Yue Zhang Xin-Zhu Fu Ming Ma Qin-Bo Qin Shao-Jun Liu

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安徽农业科学 2024年第2期52卷 221-226,240页

作者：吴志徐扬王代容韩庆斌刘平刘晓荣广东省农业科学院环境园艺研究所/广东省园林花卉种质创新综合利用重点实验室广东广州510640

[目的]从专利角度对中国苔藓产业进行了技术层面分析,以期为中国苔藓产业未来的发展提供一定的参考。[方法]以国家知识产权局和佰腾大数据开放平台为数据源,以我国苔藓产业相关的1830项专利为研究对象,对专利申请趋势、区域分布、权利... 详细信息

[目的]从专利角度对中国苔藓产业进行了技术层面分析,以期为中国苔藓产业未来的发展提供一定的参考。[方法]以国家知识产权局和佰腾大数据开放平台为数据源,以我国苔藓产业相关的1830项专利为研究对象,对专利申请趋势、区域分布、权利人及主要技术主题进行了相关分析,并对核心产业技术进行了深入分析和预测。[结果]明确了中国苔藓产业自2012年开始进入快速发展阶段;创新技术主要集中在栽培技术、中药成分、有机肥料、建筑材料、生态治理等方面;山东、江苏、安徽等省是主要技术创新区域。[结论]今后应研发出苔藓应用新产品,加强苔藓产业链上中游的技术研发,加强苔藓基础研究与应用推广。

关键词：苔藓专利分析产业技术现状建议

A H_(2)O-in-zircon perspective on the heterogeneous water content of crust-derived magmas in southern Tibet

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Science China Earth Sciences 2021年第7期64卷 1184-1194页

作者： Juntong MENG Xiaoping XIA Lin MA Ziqi JIANG Jian xu Zexian CUI qing YANG Wanfeng ZHANG Le ZHANG State Key Laboratory of Isotope Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China CAS Center for Excellence in Deep Earth Science Guangzhou 510640China College of Earth and Planetary Science University of Chinese Academy of SciencesBeijing 100049China School of Earth Science Guilin University of TechnologyGuilin 541004China

Geophysical and geochemical evidence revealed that certain amounts of water are stored in the Earth’s interior,and its distribution exhibits temporal and spatial *** studies indicate that the H_(2)O-in-zircon has a potential to reveal magma water *** secondary ion mass spectrometry(SIMS),we analyzed the zircon water content and oxygen isotopes in granitoids(two-mica granite,quartz monzonite,diorite,and granodiorite)from southern *** results are used to explore the diversity of water content in crust-derived magmas,which is also supported by the LA-ICPMS zircon trace element *** are low zircon water contents for two partial melting products of the ancient crust(peak at 85 and300 ppm,respectively).Meanwhile,there are high H_(2)O-in-zircon peaks(435 and 475 ppm,respectively)for two partial melting products of the juvenile *** calculated radiation damage accumulation in these zircon grains is below 3×10^(15)αdecay events mg^(–1),suggesting that the zircon grains are well *** is no correlation between REE+Y and H+P,indicating that the mechanism of charge balance for water uptaking into zircon,in which the excess of REE+Y to P controls Hcontent,is not applicable to the studied *** degree of magma fractionation cannot account for the zircon water content variation,because there is no co-variation between zircon Hf and H_(2)O ***,the degree of partial melting was unlikely to be responsible for the H_(2)O-in-zircon *** interpret that the H_(2)O-in-zircon variation reflects the influence of melting mode(dehydration ***-fluxed)and water content in the crustal *** the Late Devonian,dehydration melting of the crustal rocks was facilitated at elevated temperatures,which produced magmas with the lowest water ***-fluxed melting of the ancient crust would produce relatively“drier”magma than water-fluxed melting of the juvenile crust.

关键词： H_2O-in-zircon SIMS dehydration melting water-fluxed melting magma water content

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口腔楔状缺损的不同修复方式研究进展

北京口腔医学 2024年第4期32卷 301-304页

作者：卜磊青王志洁李娟谷建琦吴文慧邢台医学高等专科学校邢台054000 河北省人民医院口腔科华北理工大学

楔状缺损是牙齿硬组织常见的非龋性缺损,轻者可引起牙本质过敏,重者可引起牙髓症状。深型楔状缺损的修复分为充填、嵌体和贴面式嵌体。本文从微渗漏、抗折、粘接等方面说明了不同修复材料的优点,通过临床指标观察得出不同修复方式的优... 详细信息

楔状缺损是牙齿硬组织常见的非龋性缺损,轻者可引起牙本质过敏,重者可引起牙髓症状。深型楔状缺损的修复分为充填、嵌体和贴面式嵌体。本文从微渗漏、抗折、粘接等方面说明了不同修复材料的优点,通过临床指标观察得出不同修复方式的优势。Ⅲ度和Ⅳ度楔状缺损,用嵌体和贴面式嵌体修复缺损是一种比较好的方式,树脂基陶瓷材料结合了树脂和陶瓷的优点,具有临床使用价值。

关键词：楔状缺损嵌体树脂充填

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基于可分离替代函数算法的DOA估计方法

陕西科技大学学报 2024年第1期42卷 197-205页

作者：郑文康魏志晴白艳萍黄嘉俊禹秀梅谭秀辉王鹏中北大学数学学院山西太原030051

针对现有波达方向估计(Direction of Arrival, DOA)算法在低信噪比、多信源条件下估计精度不足、效率低等问题,提出了一种基于可分离替代函数算法的矢量水听器阵列多快拍DOA估计方法.首先对空域等角度均匀划分,构造出超完备冗余字典,建... 详细信息

针对现有波达方向估计(Direction of Arrival, DOA)算法在低信噪比、多信源条件下估计精度不足、效率低等问题,提出了一种基于可分离替代函数算法的矢量水听器阵列多快拍DOA估计方法.首先对空域等角度均匀划分,构造出超完备冗余字典,建立信号多快拍数据在空域的稀疏表示模型,然后采用可分离替代函数算法思想解决稀疏重构问题,求解出信号在空域的稀疏系数矩阵,最后将稀疏矩阵中行向量的范数映射到空域网格上,得到DOA估计值.仿真实验表明:该方法在低信噪比、多信源条件下拥有比子空间类算法、贪婪类算法以及现有凸优化类估计算法更高的DOA估计精度和更强的鲁棒性,与同类算法相比执行效率更高.

关键词： DOA估计稀疏重构压缩感知可分离替代函数算法矢量水听器

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Second-Order Phase Transition in the Two-Dimensional Classical Lattice Coulomb Gas of Half-Integer Charges

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Chinese Physics Letters 2001年第7期18卷 947-949页

作者： LUO Meng-Bo CHEN qing-Hu xu Zhu-An JIAO Zheng-Kuan Department of Physics Zhejiang UniversityHangzhou 310027

The second-order phase transition in the two-dimensional(2D)classical Coulomb gas of half-integer charges on a square lattice is investigated by using Monte Carlo *** on the finite-size scaling analysis,we estimate the second-order phase transition temperature Tc and the static critical exponentsβand v with a new numerical analysis *** precise critical temperature Tc=0.1311(2)and critical exponentsβ/v=0.1152(12)and v=0.857(15)are *** estimated value of v indicates that the charge lattice melting transition is different from the pure 2D Ising transition.

关键词： transition. method. critical

Design,synthesis and characterization of novel biodegradable macrodiols based on poly(DL-lactic acid) and poly(p-dioxanone)

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Chinese Chemical Letters 2009年第6期20卷 743-746页

作者： Chan Yu Zhang Yan Feng Luo Su Jun Wang Zhao Liu Yuan Liang Wang zhi qing Liang College of Bioengineering Chongqing University Research Center of Bioinspired Material Science and Engineering (BIMSEC) Chongqing 400030 China Department of Gynecology and Obstetrics Southwest Hospital Third Military Medical University Chongqing 400038 China

Integrating poly（lactic acid）（PLA）, glycolic acid （GA） and ethylene glycol （EG） will hopefully result in a novel copolymer that combines such advantages as fastened and controllable release rate and improved flexibility together with good biocompatibility. In this study, p-dioxanone （PDO） was employed to copolymerize with DL-lactide （LA） via ring-opening melt polymerization using Sn（Oct）2 as an initiator and ethylene glycol as a co-initiator. The obtained degradable macrodiols （HO-P（LA-co-PDO）-OH） were just such a copolymer consisting of PLA, GA and EG. 1HNMR was employed to characterize the copolymers, and the effect of PDO/LA molar ratios in the feedstock on the molecular weights of HO-P（LA-co-PDO）-OH was investigated by means of endhydroxyl analysis, 1H NMR or GPC-MALLs. The results confirmed the successful synthesis of HO-P（LA-co-PDO）-OH and revealed that one end-hydroxyl of the micarodiols was donated by LA or PDO and the other one by the co-initiator EG. In addition, the molecular weights of HO-P（LA-co-PDO）-OH increased with decreasing PDO/LA ratios.

关键词： Macrodiol Poly(lactici acid) p-Dioxanone Ethylene glycol Drug delivery carder Bone morphogenetic protein