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Copper foils with gradient structure in thickness direction and different roughnesses on two surfaces fabricated by double rolling

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International Journal of Minerals,Metallurgy and Materials 2013年第12期20卷 1170-1175页

作者： xi-yong wang Xue-feng Liu Wen-jiang Zou Jian-xin xie School of Materials Science and Engineering University of Science and Technology Beijing Beijing Laboratory of Metallic Materials and Processing for Modern Transportation University of Science and Technology Beijing Key Laboratory for Advanced Materials Processing Ministry of Education) University of Science and Technology Beijing

Copper foils with gradient structure in thickness direction and different roughnesses on two surfaces were fabricated by double rolling. The two surface morphologies of double-rolled copper foils are quite different, and the surface roughness values are 61 and 1095 nm, respectively. The roughness value of matt surface can meet the requirement for bonding the resin matrix with copper foils used for flexible printed circuit boards, thus may omit traditional roughening treatment; the microstructure of double-rolled copper foils demonstrates an obviously asymmetric gradient feature. From bright surface to matt surface in thickness direction, the average grain size first increases from 2.3 to 7.4 μm and then decreases to 3.6 μm; compared with conventional rolled copper foils, the double-rolled copper foils exhibit a remarkably increased bending fatigue life, and the increased range is about 16.2%.

关键词： copper foils rolling surfaces gradient structure fatigue of materials

Epidermal characters of Tamarix L.(Tamaricaceae) from Northwest China and their taxonomic and palaeogeographic implications

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Journal of Palaeogeography 2018年第2期7卷 179-196页

作者： Jian-Wei Zhang Ashalata D'Rozario Shi-Min Duan xi-yong wang xiao-Qing Liang Bo-Rong Pan xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Department of Botany Narasinha Dutt College Turpan Eremophytes Botanical Garden Chinese Academy of Sciences School of Resource and Environmental Sciences Yuxi Normal University

The taxonomical position of species of the genus Tamarix(Tamaricaceae) has been criticized because of their gross morphological similarities(such as slender, smooth and reddish-brown branches,grey-green foliage and scale leaves), and their systematic relationships remain unclear. In this paper, the leaf epidermal features of 17 species from China are studied based on the micro-morphological characters of the epidermal cells, stomata, salt glands, papillae and epidermal hairs. According to the studies, the leaf epidermal features, together with the character of the flower, are taxonomically clearly distinct. The establishment of Tamarix albiflonum is consolidated. Tamarix korolkowi and Tamarix ramosissima have minimal differences in epidermal characters, and the former is suggested to be a junior synonym. Tamarix ramosissima, Tamarix tarimensis, Tamarix arceuthoides and Tamarix hohenackeri are most similar with respect to their leaf epidermis; considering the common morphological features, habit, distribution and especially the hybridization, it is suggested that these four species are closely genetically related and that the variations among them are probably intraspecific. The new taxonomical evidence indicates the occurrence of13 species and four variants in China. Presently, Tamarix is a typical plant of arid and semi-arid regions, but its Eocene ancestors lived in warm and humid climates in the coastal areas of the ancient Mediterranean ***, the papillae or epidermal hairs, which are outgrowths of the outer epidermal cells facilitating the leaf to respond to water stress and commonly seen in the plants growing in arid or semi-arid areas rather than the plants in warm and humid climates, are of relatively recent origin in Tamarix. The primitive species lack papillae or epidermal hairs, while in evolved species these structures are abundant. Based on the ecological adaptations of the epidermal features, the palaeogeographic implications of Tamarix in the Late

关键词： Anatomy Arid region Epidermis Ecological adaptation Phylogenetic evolution Tamarix Northwest China

Effects of Rare Earth and Hot Pressing Sintering Temperature on the Transverse Rupture Strength of Fe-based Diamond Composites

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厦门大学学报（自然科学版） 2002年第S1期41卷 76-77页

作者： DAI Qiu-lian, LUO Can-ben, XU xi-peng, wang yong-chu (College of Mechanical Engineering & Automation, Huaqiao University, Quanzhou 362011, China)

Effects of sintering temperature in hot pressing, t yp es, states and amounts of rare earth as well as TiH 2 on the transverse rupture strength (TRS) of Fe-based composites are studied by means of orthogonal test and variance analysis in this paper. It is found that sintering temperature has a significant effect on the TRS of Fe-based diamond composites. The optimal sin tering temperature is 780～860 ℃. On the contrary, the effects of RE additi v es on values of TRS of the diamond composites have on distinct difference no mat ter the RE is in the state of mixture or compound or oxidization. Experimental r esults demonstrate that Fe-based diamond composites with RE additives exhibit h igher TRS, which results in an increase in diamond retention capacity. The degre e of increment of TRS is different at different sintering temperatures. The opti mal amount of rare earth was found to be about 1% in weight. The effect of RE is more significant at lower sintering temperature. The experimental results also reveal that TiH 2 additive has a negative effect on the TRS of Fe-based compos ites. Microscope observations demonstrate that specimen without TiH 2 additives , shows fewer pores and denser structures in the base metal. It can also be seen from the SEM observation of the resulting fracturing surface of bending test sp ecimens that the bonding of the diamond-matrix interface is better in the speci men without TiH 2 than in the specimen with TiH 2. Also the fracture surface o f the specimen without TiH 2 reveals ductile cup and cone behavior.

关键词： rare earth sintering temperature transverse rup ture strength diamond impregnated composite

Second-look arthroscopic evaluation of the articular cartilage after primary single-bundle and double-bundle anterior cruciate ligament reconstructions

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Chinese Medical Journal 2011年第21期124卷 3551-3555页

作者： wang Hai-jun AO Ying-fang CHEN Lian-xu GONG xi wang yong-jian MA yong LEUNG Kevin Kar Ming YU Jia-kuo Institute of Sports Medicine Peking University Third Hospital Beijing 100191 China

Background Several reports have shown the progression of articular cartilage degeneration after anterior cruciate ligament （ACL） reconstruction. No report has been published about the cartilage comparing changes after single-bundle （SB） and double-bundle （DI3） ACL reconstructions. The purpose of this study was to evaluate the articular cartilage changes after SB and DB ACL reconstructions by second-look arthroscopy. Methods Ninety-nine patients who received arthroscopic ACL reconstruction were retrospectively reviewed at an average of 14 months after reconstruction, 58 patients underwent SB ACL reconstruction and 41 patients underwent DB ACL reconstruction. Hamstring tendon autografts were used in all patients. Second-look arthroscopy was done in conjunction with the tibial staple fixation removal at least one year after the initial ACL reconstruction. Arthroscopic evaluation and grading of the articular cartilage degeneration for all patients were performed at the initial ACL reconstruction, and at the second-look arthroscopy. Results The average cartilage degeneration at the patellofemoral joint （PFJ） was found significantly worsened after both SB and DB ACL reconstructions. This worsening were not seen at medial tibiofemoral joint （TFJ） and lateral TFJ. Grade II cartilage damage was the most common. At second-look arthroscopy, the average patellar cartilage degeneration was 1.14±0.14 （at first look 0.52±0.11） for the SB group, and 1.22±0.15 （at first look 0.56±0.12） for the DB group. The average trochlear cartilage degeneration was 1.05±0.16 （at fist look 0.10±0.06） and 0.66±0.17 （at fist look 0.17±0.09）, respectively. The average patellar cartilage degeneration showed no significant difference in both groups. However, the average trochlea cartilage degeneration in DB group was significantly less than in SB group. Conclusions Patellofemoral cartilage degeneration continued to aggravate after ACL reconstruction. DB ACL reconstruction could significantly decrease t

关键词： anterior cruciate ligament single bundle double bundle patellofemoral joint cartilage second-look arthroscopy

Phase separation in solvent extraction of cobalt from acidic sulfate solution using synergistic mixture containing dinonylnaphthalene sulfonic acid and 2-ethylhexyl 4-pyridinecarboxylate ester

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Transactions of Nonferrous Metals Society of China 2019年第5期29卷 1107-1116页

作者： Ting HUANG yong-xi wang Hui-ping HU Fang HU Yu-qing LUO Shi-jun LIU College of Chemistry and Chemical Engineering Central South UniversityChangsha 410083China

Phase separation rate is a critical character in determining the usefulness of a solvent extraction system in hydrometallurgy. A survey of the synergistic mixture containing dinonylnaphthalene sulfonic acid (HDNNS) and 2-ethylhexly 4-pyridinecarboxylate ester (4PC) for the extraction of cobalt from acidic single metal sulfate solution was carried out to suggest how the physicochemical properties and the morphology of the reverse micelles in the loaded organic phase affect the phase separation. The results show that effective parameters affecting the phase separation are the viscosity and the excess water uptake of the loaded organic phase. It is obvious that the specific settling rate (SSR) decreases with the apparent increase of these two parameters. The measurement of small angle X-ray scattering (SAXS) proves that the morphology of the reversed micelles in the loaded organic phase changes evidently with the change of the specific settling rate (SSR).

关键词： synergistic solvent extraction phase separation specific settling rate reverse micelle cobalt

Comparative study on early period of recovery between minimally invasive surgery total knee arthroplasty and minimally invasive surgery-quadriceps sparing total knee arthroplasty in Chinese patients

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Chinese Medical Journal 2008年第15期121卷 1353-1357页

作者： YU Jia-kuo YU Chang-long AO Ying-fang GONG xi wang yong-jian wang Shu xiNG xie CHEN Lian-xu JU xiao-dong Institute of Sports Medicine of Peking University Third Hospital Institute of Sports Medicine of Peking University Beijing 100083 China

Background Different kinds of minimally invasive surgery （MIS） procedures have now been used in total knee arthroplasty （TKA）. Compared with traditional TKA procedure with a long skin incision, clinical studies showed MIS procedures had some advantages. Quadriceps sparing （QS） procedures are the most minimally invasive MIS procedure until now. This study was aimed to find the insertion types for Chinese patients＇ vastus medialis and if the QS procedure had some advantages in patients＇ early recovery. Methods Between February 2006 and May 2007, 120 consecutive patients underwent unilateral primary TKA under general anesthesia, among whom 14 patients were lost to follow-up, the remaining 106 cases were enrolled in this study. Among the 106 cases there were 85 right knees, 21 left knees （15 men and 91 women, with a mean age of 65.1±7.4 years）; osteoarthritis in 97 patients （91.5%） and rheumatoid arthritis in 9 patients （8.5%）. MIS TKA was performed in 49 cases （MIS TKA group）, while MIS-QS TKA in 57 cases （MIS-QS TKA group）. During the operation, the type Ⅰ, Ⅱ and Ⅲ insertions of the vastus medialis for all patients were recorded. Each knee was rated post-operatively according to the Hospital of Special Surgery （HSS） scoring system. Clinical follow-up was undertaken at 1 week, 2, 6, 12 and 24 weeks. Operating time and complications were recorded. Results There was no statistically significant difference between the two groups for gender distribution, age, left or right knee incidence, pre-operative diagnosis, incidence of varus or valgus deformity. Of the 106 cases there was 1 （0.9%） case with a type Ⅰ insertion of the vastus medialis, 4 （3.8%） cases with type Ⅱ insertions, 101 （95.3%） cases with type Ⅲ insertions. The HSS scoring was significantly different between the MIS-QS TKA group and MIS TKA group within the first two weeks post operation. From 2 weeks later to 24 weeks, no significant difference was found. The average operating time was （53.3±12.4） minutes in t

关键词：关节造形术四头肌中国外科手术

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并联机器人运动目标精确优化定位仿真研究

计算机仿真 2017年第10期34卷 320-324,329页

作者：王映知周翕王永贾平中国科学技术大学信息科学技术学院安徽合肥230026

并联机器人具有精度高等优点,被广泛应用于大口径望远镜副镜的姿态调整中,并联机器人的末端精度决定了望远镜副镜的姿态精度,是最重要的性能指标。制造和安装过程中不可避免的机构误差会导致并联机器人的定位误差问题。为有效提高末端精... 详细信息

并联机器人具有精度高等优点,被广泛应用于大口径望远镜副镜的姿态调整中,并联机器人的末端精度决定了望远镜副镜的姿态精度,是最重要的性能指标。制造和安装过程中不可避免的机构误差会导致并联机器人的定位误差问题。为有效提高末端精度,需进行精度补偿。通过闭环矢量法,建立机构误差与输出位姿误差之间的关系,将精度补偿问题转化为多参数组合优化问题。同时,考虑位姿对雅可比矩阵的影响,在优化过程中对雅可比矩阵实时更新。利用优化得到的杆长补偿量来调整机器人名义杆长规划量,从而提高机器人的运动精度。针对梯度下降法收敛速度慢,标准粒子群算法易陷入局部最优的问题,提出了一种改进的混合粒子群算法来解该优化问题。仿真结果表明该混合粒子群算法收敛较快,能有效避免陷入局部最优,并且可以明显改善普通粒子群算法的性能,补偿后并联机器人的定位精度得到了有效提高。

关键词：并联机器人误差补偿混合粒子群算法

EZH2-dependent myelination following sciatic nerve injury

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Neural Regeneration Research 2025年第8期20卷 2382-2394页

作者： Hui Zhu Li Mu xi Xu Tianyi Huang Ying wang Siyuan Xu Yiting wang Wencong wang Zhiping wang Hongkui wang Chengbin Xue Research Center of Clinical Medicine Affiliated Hospital of Nantong UniversityKey Laboratory of Neuroregeneration of Jiangsu and Ministry of EducationCo-innovation Center of NeuroregenerationNMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology ProductsNantong UniversityNantongJiangsu ProvinceChina Medical School of Nantong University NantongJiangsu ProvinceChina Department of Neurology Affiliated Hospital of Nantong UniversityNantongJiangsu ProvinceChina Department of Rehabilitation Medicine Affiliated Hospital of Nantong UniversityNantongJiangsu ProvinceChina Department of Critical Care Medicine Nantong Fourth People’s HospitalNantongJiangsu ProvinceChina

Demyelination and remyelination have been major focal points in the study of peripheral nerve regeneration following peripheral nerve ***,the gene regulatory network of regenerated myelin differs from that of native *** of enhancer of zeste homolog 2(EZH2)hinders the differentiation,maturation,and myelination of Schwann cells in *** further determine the role of EZH2 in myelination and recovery post-peripheral nerve injury,conditional knockout mice lacking Ezh2 in Schwann cells(Ezh2^(fl/fl);Dhh-Cre and Ezh2^(fl/fl);Mpz-Cre)were *** results show that a significant proportion of axons in the sciatic nerve of Ezh2-depleted mice remain *** highlights the crucial role of Ezh2 in initiating Schwann cell ***,we observed that 21 days after inducing a sciatic nerve crush injury in these mice,most axons had remyelinated at the injury site in the control nerve,while Ezh2^(fl/fl);Mpz-Cre mice had significantly fewer remyelinated axons compared with their wild-type *** suggests that the absence of Ezh2 in Schwann cells impairs myelin formation and *** conclusion,EZH2 has emerged as a pivotal regulatory factor in the process of demyelination and myelin regeneration following peripheral nerve *** EZH2 activity during these processes may offer a promising therapeutic target for the treatment of peripheral nerve injuries.

关键词： demyelination EZH2 myelination peripheral nerve injury PRC2 remyelination Schwann cells sciatic nerve crush sciatic nerve transection

Dative B–N bonds weaven toward two-dimensional purely organic materials for single crystals

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Science China Chemistry 2025年第01期 12-14页

作者： Wei-Lei Zhou Siwei wang yong Chen College of Chemistry and Materials Science Inner Mongolia Key Laboratory of Chemistry for Nature Products and Synthesis for Functional Molecules Innovation Team of Optical Functional Molecular Devices Inner Mongolia Minzu University College of Chemistry Nankai University

Molecular topology is one of the important topics to study and understand the relationship between molecular structure and properties [1]. Particularly, two-dimensional (2D) materials with extremely high surface area and ultra-thin morphology have attracted considerable attention due to their unexpected properties in materials and chemistry [2,3].

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