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Science China Earth Sciences 2014年第6期57卷 988-998页

作者： hou SuKuan DENG Tao HE Wen CHEN ShanQin Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of Sciences Hezheng Paleozoological Museum

The skull and mandible of a Late Miocene fossil pig,Chleuastochoerus,are compared morphologically with those of extant pigs and peccaries,and subjected to a functional *** presence of a rostral bone in the skull and relatively strong rostral muscles indicates that Chleuastochoerus possessed considerable digging ability,though the relatively narrow occipital surface and the shortness of the skull would have restricted the range of motion through which the skull could be *** distinctive pre-zygomatic plate and over-canine arch-niche may have played a role in protecting the skull and canines during *** massive masticatory muscles,reconstructed based on well-developed parietal and zygomatic crests,would have enabled the mouth to close quickly and contributed to moving the mandible both longitudinally and *** configuration of the cranio-mandibular joint and its relatively high position show clearly that Chleuastochoerus was capable of both crushing and grinding movements during *** comparatively simple structure of the crown surfaces of the cheek teeth suggests that the food of Chleuastochoerus may have been softer than that of extant *** diet of Chleuastochoerus is postulated to fall between those of true forest pigs and open habitat pigs,and the habitat of Chleuastochoerus to be relatively humid forest edge or nearby areas of open steppe.

关键词： Suidae Late Miocene Linxia Basin morpho-functional analysis foraging behavior

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Oxadiazole-Functionalized Polyacrylonitrile Fiber as Selective Adsorbent for Mercury Ion

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天津大学学报：英文版 2020年第1期26卷 49-56页

作者： Liping hou Minli Tao School of Sciences Tianjin University

A new oxadiazole-functionalized polyacrylonitrile fiber(PANAOF)was successfully fabricated by immobilizing the organic molecule 2-chloromethyl-5-phenyl-1,3,4-oxadiazole on aminated fiber(PANAF).The fibers were characterized completely by Fourier-transform infrared spectroscopy,elemental analysis,X-ray diffraction,and X-ray photoelectron spectroscopy *** with PANAF,PANAOF showed a higher adsorption capability for Hg^2+ions in aqueous *** functionalized fiber PANAOF exhibited a highly selective adsorption for Hg^2+when coexisting with other metal ions ***^2+,Cd^2+,Cu^2+,Zn^2+,Ni^2+,Co^2+,Cr^3+,Ca^2+,and Mg^2+.The PANAOF presented the best adsorption capacity for Hg^2+at pH ***,the adsorption experimental data fit well with the pseudo-second-order kinetic model and Langmuir ***,the PANAOF almost retained its original adsorption capacity(112 mg/g)after five cycles,indicating its excellent reusability in practical applications.

关键词： Polyacrylonitrile fiber Mercury Adsorption 1,3,4-oxadiazole Selectivity

Field observations of the thermal stability of permafrost under buildings with an underfloor open ventilation space and pile foundations in warm permafrost at high altitudes

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Advances in Climate Change Research 2023年第2期14卷 267-275页

作者： Xin hou Ji CHEN Yu SHENG Peng-Fei RUI You-Qian LIU Shou-Hong ZHANG Tian-Chun DONG Jia-wei GAO Beiluhe Observation and Research Station of Frozen Soil Engineering and Environment State Key Laboratory of Frozen Soil EngineeringNorthwest Institute of Eco-Environmental and ResourcesChinese Academy of SciencesLanzhou 730000China China Railway QinghaieTibet Group Co.Ltd Xining 810007China University of Chinese Academy of Sciences Beijing 100049China

Pile foundations combined with ventilation spaces under floors are the most common method in buildings over *** safety and stability of buildings are closely related to the temperature of ***,there are limitations of understanding on this method in the high-altitude,warm(>−1℃)permafrost areas on the Qinghai–Tibet *** this study,the thermal stability of permafrost foundation soils under buildings with an underfloor open ventilation space and pile foundations in warm permafrost at high altitudes was studied through field observations of ground and air temperatures,wind speed,net radiation from 2017 to *** results indicated that the open ventilation space exerted an effective cooling effect on the underlying permafrost and pile foundations from March to October,while a thermal insulation effect was observed from November to February of the following year,but overall,the cooling effect dominated;the cooling effect of open ventilation spaces differed *** permafrost temperature on the south-facing side was higher than that on the north-facing side,and those on the east and west sides were higher than that directly under the open ventilation space of the *** study also demonstrated that radiation shielded by the building was a main factor of the cooling effect of open ventilation spaces,and the cooling effect of open ventilation spaces could accelerate the back-freezing of the cast-in-place(CIP)pile *** structure could effectively maintain the frozen state of the underlying warm permafrost at high elevations on the interior Qinghai–Tibet Plateau.

关键词： Warm permafrost Infrastructure Open ventilation space Pile foundation Cooling effect

A Separation Theorem for Stochastic Singular Linear Quadratic Control Problem with Partial Information

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Acta Mathematicae Applicatae Sinica 2013年第2期29卷 303-314页

作者： Hong-ji MA Ting hou College of Science Shandong University of Science and Technology Department of Systems and Control Beijing University of Aeronautics and Astronautics

In this paper, we provide a separation theorem for the singular linear quadratic （LQ） control problem of ItS-type linear systems in the case of the state being partially observable. Above all, the Kalmam Bucy filtering of the dynamics is given by means of Girsanov transformation, by which the suboptimal feedback control of the LQ problem is determined. Furthermore, it is shown that the well-posedness of the LQ problem is equivalent to the solvability of a generalized differential Riccati equation （GDRE）.

关键词： singular optimal control Kalman-Bucy filtering separation theorem linear systems generalizeddifferential Riccati equation

Chemoenzymatic Synthesis of Cellular Adhesion Tripeptide RGD Precursor in Organic Media

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Chemical Research in Chinese Universities 2006年第6期22卷 721-726页

作者： WANG Hua ZHAO Mi-feng PU Li-mei DING wei HUANG Yi-bing hou Rui-zhen ZENG Hong-bin XU Li ZHANG Xue-zhong Key Laboratory of Molecular Enzymology and Engineering Jilin University Changchun 130021 P. R. China China-Japan Union Hospital Jilin University Changchun 130033 P. R. China First Hospital Jilin University Changchun 130021 P. R. China

Chemoenzymatic synthesis of tripeptide Bz-RGD-（OEt）2 was conducted in this study. First, the free dipeptide Gly-Asp was synthesized via a novel chemical method, wherein only L-aspaxtic acid was used and was followed by the esterification of Gly-Asp. The formation of the linkage between the third amino acid Bz-Arg-OEt and Gly-Asp-（OEt）2 was completed by using the enzymatic method in organic media. The effects of several factors such as pH, the water content, triethylamine （TEA）, the molar ratio of the substrates, and the reaction time on the yield of Bz-RGD- （OEt）2 were examined. It was obtained that the optimum conditions for Bz-RGD-（OEt）2 synthesis in an ethanol/ Tris-HC1 buffer system （ volume ratio 93： 7 ） were as follows ： pH = 8.0 ; temperature, 30 ℃ ; reaction time, 7 h. The tripeptide yield was 75.2%.

关键词： RGD Synthesis Trypsin Organic solvent

Analytic Invariant Curves for an Iterative Equation Related to Ricker-type Second-order Equation

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Acta Mathematica Sinica,English Series 2021年第7期37卷 1041-1052页

作者： hou Yu ZHAO Michal FECKAN School of Mathematics Chongqing Normal UniversityChongqing 401331P.R.China Department of Mathematical Analysis and Numerical Mathematics Comenius University in BratislavaMlynska dolina84248 BratislavaSlovakia Mathematical Institute of Slovak Academy of Sciences Stefanikova 4981473 BratislavaSlovakia

In this paper,we consider the existence of analytic invariant curves of an iterative equation f(f(x))=xea-x-f(x)which arises from Ricker-type second-order *** reducing the equation with the Schr?der transformation to an auxiliary equation,the author discusses not only that the parameter at resonance,i.e.,at a root of the unity,but also the parameter near resonance under the Brjuno condition.

关键词： Difference equation invariant curves analytic solution small divisor

Unusual presentation of urachal adenocarcinoma with genitourinary cutaneous metastasis

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Asian Journal of Andrology 2015年第2期17卷 339-340页

作者： Yin-Hui Yang Yan Zhu Xiang-wei Zhu Hong-Juan Tang Jian-Guo hou Wan-Hai Xu Department of Urology The Fourth Hospital of Harbin Medical University Harbin China Department of Urology Department of Pathology Changhai Hospital Second Military Medical University Shanghai China.

Dear Editor, The urachus, which is a vestigial structure between the dome of the bladder and umbilicus, usually, retracts from the bladder before birth. However, the urachal remnant was continuous with the bladder cavity even in adults in 32% of bladder in one autopsy study.1 For this reason, tumors may develop from the remnants, most of which are well-differentiated mucinous adenocarcinomas, which is a rare form of vesical malignancy, accounting for 〈 1% of all bladder cancers. Although local spread to the peritoneum is common at presentation, distant metastases without local recurrence are rarely detected following surgical excision of clinically localized disease. To the best of our knowledge,

关键词： MUCINOUS ADENOCARCINOMA CARCINOMA

Ag_(2)O/PPh_(3)/TBD催化合成3,6-二氮杂二环[3.2.1]辛烷衍生物

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广东化工 2024年第7期51卷 11-13,23页

作者：侯良宁钟玮张凯强王宁周鸿池王海飞湖南工业大学生命科学与化学学院湖南株洲412007

五元含氮杂环是吲哚生物碱和药物中间体分子中的一个重要的结构单元,在过去几十年中,单环的吡咯烷的合成已有大量的文献报道,其中甲亚胺叶立德与缺电子烯烃之间的1,3-偶极环加成是最常用的制备丰富多样吡咯烷的方法,但带有吡咯烷结构的... 详细信息

五元含氮杂环是吲哚生物碱和药物中间体分子中的一个重要的结构单元,在过去几十年中,单环的吡咯烷的合成已有大量的文献报道,其中甲亚胺叶立德与缺电子烯烃之间的1,3-偶极环加成是最常用的制备丰富多样吡咯烷的方法,但带有吡咯烷结构的二环化合物的合成却少有报道。本文以不同系列的偶氮甲碱叶立德与a-取代的末端烯烃酰胺为原料,Ag(I)/PPh_(3)为催化体系,在有机或无机碱的作用下,一步实现了消旋体3,6-二氮杂二环[3.2.1]辛烷衍生物的合成。与现有方法相比,本实验方法步骤简单,原料廉价易得,反应条件温和,底物适应性广。

关键词：氧化银吡咯烷 [3+2]环加成偶氮甲碱叶立德 3 6-二氮杂二环[3.2.1]辛烷

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双曲面斜交网格筒冷却塔施工关键技术

施工技术（中英文） 2024年第2期53卷 74-78页

作者：侯彦果朱博莉郭宇飞刘亚洲高巍清华大学土木工程系北京100084 北京科技大学土木与资源工程学院北京100083 长江精工(上海)建筑科技有限公司上海200233

冷却塔应用在电力行业,其形态多为双曲面或锥台形曲面,结构组成兼具高耸和大跨特点,施工难度大,对精度控制有较高要求。结合某双曲面斜交网格筒冷却塔工程,介绍其钢结构施工关键技术,主要包括冷却塔拼装、吊装技术,施工过程中结构临时... 详细信息

冷却塔应用在电力行业,其形态多为双曲面或锥台形曲面,结构组成兼具高耸和大跨特点,施工难度大,对精度控制有较高要求。结合某双曲面斜交网格筒冷却塔工程,介绍其钢结构施工关键技术,主要包括冷却塔拼装、吊装技术,施工过程中结构临时加强措施及冷却塔蒙皮施工技术。基于施工全过程分析,验证施工方案可行性和高效性。

关键词：冷却塔钢结构拼装吊装施工技术

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大肠杆菌肌苷酸节点代谢优化高效合成肌苷

食品与发酵工业 2024年第4期50卷 44-50页

作者：刘铁重高志强侯德欣谢希贤吴鹤云天津科技大学生物工程学院天津300457 工业发酵微生物教育部重点实验室(天津科技大学) 天津300457

该研究以产肌苷的大肠杆菌INO4-5为出发菌,针对其发酵过程中副产物含量高、肌苷产量低以及需要额外添加腺嘌呤等问题,对肌苷酸节点代谢流进行了优化。首先使用不同启动子和核糖体结合位点对枯草芽孢杆菌来源的purA_(bsu)基因进行了表达... 详细信息

该研究以产肌苷的大肠杆菌INO4-5为出发菌,针对其发酵过程中副产物含量高、肌苷产量低以及需要额外添加腺嘌呤等问题,对肌苷酸节点代谢流进行了优化。首先使用不同启动子和核糖体结合位点对枯草芽孢杆菌来源的purA_(bsu)基因进行了表达,以强化腺苷合成支路,使菌株5 L发酵罐上的肌苷产量达到了29.5 g/L,且无需额外添加腺嘌呤。接着通过替换guaB基因的原有启动子以弱化鸟苷合成支路,并过表达guaC基因促使鸟苷酸回流至肌苷酸,使菌株副产物含量显著降低且肌苷产量提升至35.1 g/L;最后对不同5′-核苷酸酶进行了筛选和强化,发现引入来自酿酒酵母的特异性5′-核苷酸酶基因(introduction of specific 5′-nucleotidase gene,ISN1)可有效促进肌苷生产。最终所得菌株INO7-6在5 L发酵罐上发酵,肌苷产量为41.2 g/L,转化率为0.17 g/g葡萄糖,生产强度为0.86 g/(L·h),为目前报道的基因工程菌株的最高产量。

关键词：肌苷肌苷酸大肠杆菌代谢工程发酵