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冷拉拔Cu-2.5% Fe-0.2% Cr和Cu-6% Fe合金的显微组织与性能（英文）

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2015年第8期16卷 622-629页

作者： Guo-huan BAO Yi CHEN Ji-en MA You-tong fanG Liang MENG Shu-min ZHAO xin WANG Jia-bin LIU Department of Materials Science and Engineering Zhejiang University College of Electrical Engineering Zhejiang University College of Materials and Environmental Engineering Hangzhou Dianzi University

目的:探索Cu-Fe合金中纳米尺寸和微米尺寸的Fe相的变形行为及区别。方法:1.通过热处理在Cu-2.5%Fe-0.2%Cr合金中得到纳米级的Fe析出相,在Cu-6%Fe中得到微米级的Fe析出相;2.通过冷拉拔手段使铜合金从棒状逐步变形成线材;3.使用光学显微... 详细信息

目的:探索Cu-Fe合金中纳米尺寸和微米尺寸的Fe相的变形行为及区别。方法:1.通过热处理在Cu-2.5%Fe-0.2%Cr合金中得到纳米级的Fe析出相,在Cu-6%Fe中得到微米级的Fe析出相;2.通过冷拉拔手段使铜合金从棒状逐步变形成线材;3.使用光学显微镜、扫描电镜和透射电镜观察微观组织,并用万能电子试验机测量抗拉强度,用标准四点法测量电阻率。结论:1.通过热处理在Cu-6%Fe合金中得到尺寸约50 nm的初生Fe颗粒,在Cu-2.5%Fe-0.2%Cr合金中得到尺寸约50 nm的次生Fe颗粒;2.初生Fe颗粒在冷拉拔过程中转变成丝带状纤维,Cu/Fe相界面密度随变形量增加而增加,从而使Cu-6%Fe合金的强度和电阻率都随之增大;3.次生Fe颗粒即使在η=6的时候也难以变形,保持着球形的形貌,同时高密度的位错环绕着Fe颗粒;Cu-2.5%Fe-0.2%Cr合金的强度随变形量增加而增大,遵循Orowan强化机制;Cu-2.5%Fe-0.2%Cr合金的电阻率几乎保持不变,因为Cu/Fe相界面密度在冷拉拔过程中几乎不变;4.尺寸效应和Fe析出颗粒与Cu基体的非共格界面对Fe析出颗粒在冷拉拔过程中不变形起到重要作用。

关键词：铜合金变形显微组织强度

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全方向推进器主要参数对其水动力性能的影响

哈尔滨工程大学学报 2005年第6期26卷 713-716页

作者：常欣黄胜贡毅敏哈尔滨工程大学船舶工程学院黑龙江哈尔滨150001

为优化全方向推进器的模型设计,采用面元法分析全方向推进器主要参数的变化对非定常水动力性能的影响.基于螺旋桨面元法理论建立了全方向推进器的非定常水动力性能计算的数学模型,进行了数值预报,采用关于扰动速度势的基本积分微分方程... 详细信息

为优化全方向推进器的模型设计,采用面元法分析全方向推进器主要参数的变化对非定常水动力性能的影响.基于螺旋桨面元法理论建立了全方向推进器的非定常水动力性能计算的数学模型,进行了数值预报,采用关于扰动速度势的基本积分微分方程,以双曲面元消除面元间的缝隙,在桨叶随边满足压力Kutta条件.应用Morino解析公式计算面元的影响系数,用Yanagizawa方法求得物体表面上的速度分布.分析了全方向推进器主要参数对水动力性能的影响.计算结果表明,周期螺距角的值对全方向推进器的非定常水动力性能起决定性作用.该文的计算结果可以作为下一步试验研究的基础.

关键词：全方向推进器面元法速度势整体螺距角周期螺距角非定常

Mechanism of anti-tumor effect of HIF-1α silencing on cervical cancer in nude mice

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The Chinese-German Journal of Clinical Oncology 2010年第7期9卷 416-421页

作者： Yanxiang Cheng Wen fan Bingshu Li Qin Wang min Hu Li Hong Department of Gynecology Renmin Hospital of Wuhan University Wuhan 430060 China

Objective： The aim of our study was to observe the anti-tumor effect of silencing the expression of HIF-1α on cervical cancer in nude mice and to explore its mechanism of action. Methods： Human cervical cancer cell line Siha cells were divided into 3 groups： mock control group, control group transfected with scrambled sequence plasmid, and experimental group transfected with pU-HIF-la-shRNA eukaryotic expression plasmid. Cultured cells of the three groups were inoculated in nude mice to establish cervical cancer-bearing nude mice. HIF-la RNAi assay was performed to evaluate the tumor-suppressive effect of HIF-1α silencing on cervical cancer-bearing nude mice. Immunohistochemistry and Western blot were used to observe the distribution and protein expression of HIF-1α and GLUT1, while RT-PCR was adopted to detect the gene expression of HIF-1α, GLUTI and HK I1. The product of glycolysis （tactic acid） and apoptosis in tumor cells were detected by colorimetry and semi-quantitative TUNEL staining, respectively. Results： The tumor growth in experimental group was significantly slower than that in the two control groups （P 〈 0.05）. In the 50th day after transplantation, the tumor weight in the experimental group was （1.90 ± 0.28） g, significantly lower than （2.95 ± 0.77） g in the control group and （2.54 ± 0.56） g in the mock group （P 〈 0.01）. In the experimental group, the gene and protein levels of HIF-1α were 0.45 ± 0.04 and 1.25 ± 0.92, and the levels of GLUT1 were 0.32 ± 0.02 and 1.25 ± 0.48, respectively. Both indicators in HIF-la and GLUT1 were lower than that in the two control groups （P 〈 0.05）. The expression levels of HK Ⅱ gene and lactic acid in the experimental group were lower than that in the two control groups （P 〈 0.05）, but the apoptotic cells were much more numerous in the experimental group than that in matched control groups （P 〈 0.01）. Conclusion： The 9ene therapy by siRNAtargeted silencing of HIF-1α may down-regulate its downstream genes GLUT1 and HK Ⅱ

关键词： cervical neoplasms HIF-1α GLUTI RNAi technique nude mice

Morphological evolution and growth kinetics of Kirkendall voids in binary alloy system during deformation process-Phase field crystal simulation study

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Transactions of Nonferrous Metals Society of China 2017年第3期27卷 599-607页

作者： Wen-jing MA Chang-bo KE Shui-bao LIANG min-bo ZHOU xin-ping ZHANG School of Materials Science and Engineering South China University of Technology Guangzhou 510640 China

The formation and growth of Kirkendall voids in a binary alloy system during deformation process were investigated byphase field crystal *** simulation results show that Kirkendall voids nucleate preferentially at the interface,and the averagesize of the voids increases with both the time and strain *** is an obvious coalescence of the voids at a large strain rate whenthe deformation is applied along the interface under both constant and cyclic strain rate *** the cyclic strain rate appliedalong the interface,the growth exponent of Kirkendall voids increases with increasing the strain rate when the strain rate is largerthan1.0×10-6,while it increases initially and then decreases when the strain rate is smaller than9.0×10?*** growth exponent ofKirkendall voids increases initially and then decreases gradually with increasing the length of cyclic period under a square-waveform constant strain rate.

关键词： Kirkendall void binary alloy phase field crystal method growth exponent deformation

Free peroneal perforator-based sural neurofasciocutaneous flaps for reconstruction of hand and forearm

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Chinese Medical Journal 2009年第14期122卷 1621-1624页

作者： CAI Pei-hua LIU Sheng-he CHAI Yi-min WANG Hai-ming RUAN Hong-jiang fan Cun-yi Department of Orthopedic Surgery Sixth People's Hospital Shanghai Jiao Tong University Shanghai 200233 China

Background Sural neurofasciocutaneous flap has been popularly used as an excellent option for the coverage of soft tissue defects in the lower third of leg, ankle and foot, but its free transplantation has been rarely reported. The objective of our work was to investigate the operative technique and clinical results of repairing the soft tissue defects of hand and forearm with free peroneal perforator-based sural neurofasciocutaneous flap. Methods Between May 2006 and March 2007, 10 patients including 7 men and 3 women were treated. Their ages ranged from 22 to 51 years. They presented to emergency with large soft tissue defects of 16 cm × 7 cm to 24 cm × 10 cm in size in hand and forearm after injured by motor vehicle accidents （2 cases） or crushed by machine （8 cases）. Thorough debridements and primary treatments to associated tendon ruptures or bone fractures were performed on emergency. And free peroneal perforator-based sural neurofasciocutaneous flaps were transplanted when the wound areas were stable at 5 to 7 days after emergency treatment. The flaps were designed along the axis of the sural nerve according to the shape and size of the soft tissue defects, with the peroneal perforator above the lateral malleolus as the pedicle and along with a part of the peroneal artery for vascular anastomosis. Then the flaps were harvested to repair the recipient sites with the peroneal artery anastomosed to the radial （or ulnar） artery and the peroneal veins to one of the radial （or ulnar） veins and the cephalic vein respectively. The flap sizes ranged from 18 cm × 8 cm to 25 cm × 12 cm. The donor areas were closed by skin grafts. Results All of the 10 flaps survived after surgeries. Marginal necrosis occurred in only 2 cases. The skin grafts survived entirely in the donor sites, and no obvious influence on the donor legs was observed. All of the transplanted flaps presented favourable contours and good functions at 9 to 12 months＇ follow-up. Conclusions Peroneal perfora

关键词： free transplantation peroneal perforator sural neurofasciocutaneous flap soft tissue defect

Hyperpolarization-activated cyclic nucleotide-gated 2 contributes to electroacupuncture analgesia on lumbar disc herniation-induced radicular pain through activation of microglia in spinal dorsal horn

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Journal of Traditional Chinese Medicine 2022年第3期42卷 372-378页

作者： QIN Qingguang CHEN Zujiang fan Weimin LI Junhua LIAO Liqing LI Yikai School of Traditional Chinese Medicine Southern Medical UniversityGuangzhou 510515China

OBJECTIVE:To explore the mechanisms of dorsal root ganglia and spinal microglia cascade cross in electroacupuncture(EA)analgesia in the treatment of lumbar disc ***:A rat model of lumbar disc herniation(LDH)was established,EA was administered at Huantiao(GB30)acupoint 30 min once a day,for 3 *** and after modeling,and after EA,mechanical allodynia thresholds were ***-activated cyclic nucleotide-gated 2(HCN2)in dorsal root ganglia was detected by quantitative polymerase chain reaction(qPCR)and Western blot.C-X3-C motif chemokine ligand 1(CX3CL1)and activity of microglia in spinal cord was observed separately via qPCR and immunofluorescence ***:The mechanical allodynia threshold of the right planta of model rats was significantly reduced(P<0.01),EA increased the mechanical pain threshold of rats(P<0.01),and decreased HCN2 mRNA,and protein expression,reduced the expression of CX3CL1 and the activation of ***7288(a blocker of HCN channel)reduced the analgesic effect of EA from 1.83±0.84 to 0.74±0.20(P<0.05),and the expression of CX3CL1 in the spinal cord decreased from 0.52±0.11 to 0.15±0.05(P<0.01).CONCLUSION:EA analgesia on the radicular pain of LDH is *** reduced the expression of HCN2 channel in the dorsal root ganglion,thereby decreasing the noxious stimulation entered to microglia in spinal dorsal *** work supports EA is an effective treatment for radicular pain of LDH.

关键词： intervertebral disc displacement radicular pain electroacupuncture ganglia,spinal hyperpolarization-activated cyclic nucleotide-gated channels microglia

长梁山隧道F_(26)断层施工超前地质预报

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铁道工程学报 2007年第12期24卷 14-18页

作者：辛民高铁道第三勘察设计院集团有限公司天津300142

研究目的:在隧道施工中,准确预报施工前方地质条件,尤其是区域断层的规模、性质和影响范围,将影响施工质量、工期与安全。研究方法:在采用针对性地质调绘、掌子面素描、综合物探、水文长期观测等综合方法基础上,进行相关性分析。研究结... 详细信息

研究目的:在隧道施工中,准确预报施工前方地质条件,尤其是区域断层的规模、性质和影响范围,将影响施工质量、工期与安全。研究方法:在采用针对性地质调绘、掌子面素描、综合物探、水文长期观测等综合方法基础上,进行相关性分析。研究结果:采用节理相关性预报断层在洞内的出现里程位置,并推导出相关公式。研究结论:经施工验证F26断层采用的综合超前预报技术是合理的、有效的;运用节理相关性分析方法,预报了断层在洞内的出现里程位置;地质超前预报应针对地质特点,选取相应的预测预报技术。

关键词：区域断层超前地质预报信息化施工

Comparison of two vasopressor protocols for preventing hypotension post-spinal anesthesia during cesarean section: a randomized controlled trial

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Chinese Medical Journal 2021年第7期134卷 792-799页

作者： Qian-Qian fan Yong-Hui Wang Jing-Wen Fu Hai-Long Dong Man-Ping Yang Duo-Duo Liu Xiao-fan Jiang Zhi-xin Wu Li-Ze Xiong Zhi-Hong Lu Department of Anesthesiology and Perioperative Medicine Xijing HospitalFourth Military Medical UniversityXi’anShaanxi 710032China Department of Gynecology and Obstetrics Xijing HospitalFourth Military Medical UniversityXi’anShaanxi 710032China Department of Neurosurgery Xijing HospitalFourth Military Medical UniversityXi’anShaanxi 710032China Department of Anesthesiology and Translational Research Institute of Brain and Brain-like Intelligence Shanghai Fourth People’s Hospital Affiliated to Tongji University School of MedicineShanghai 200081China.

Background:Norepinephrine infusion decreases hypotension after spinal anesthesia during cesarean *** study aimed to compare the efficacy of norepinephrine infusion and ephedrine bolus against post-spinal hypotension in ***:In this double-blinded,randomized controlled clinical trial,parturients scheduled for elective cesarean section were randomly allocated to receive norepinephrine infusion(0.05μg·kg^(-1)·min^(-1))just before spinal anesthesia continuing for 30 min or ephedrine bolus(0.15 mg/kg)just before spinal anesthesia.A rescue bolus(5μg norepinephrine for the norepinephrine group,and 5 mg ephedrine for the ephedrine group)was administered whenever hypotension *** primary outcome was the incidence of hypotension within 30 min of spinal anesthesia *** outcomes included maternal and neonatal outcomes 30 min after spinal block,and neonatal cerebral oxygenation 10 min after ***:In total,190 patients were enrolled;of these patients,177 were included in the final *** patients suffered hypotension in the norepinephrine group than in the ephedrine group(29.5%vs.44.9%,odds ratio[OR]:0.51,95%confidence interval[CI]:0.28-0.95,P=0.034).Moreover,the tachycardia frequency was lower in the norepinephrine group than in the ephedrine group(OR:0.22,95%CI:0.11-0.44,P<0.001),and patients suffered less nausea and vomiting(OR:0.28,95%CI:0.11-0.70,P=0.004).There was no difference in Apgar scores and umbilical arterial blood gas analysis between the two ***,neonatal cerebral regional saturations were significantly higher after birth in the norepinephrine group than in the ephedrine group(mean difference:2.0%,95%CI:0.55%-3.45%,P=0.008).Conclusion:In patients undergoing elective cesarean section with spinal anesthesia,norepinephrine infusion compared to ephedrine bolus resulted in less hypotension and tachycardia,and exhibited potential neonatal benefits.

关键词： Hypotension Spinal anesthesia Norepinephrine Ephedrine Cesarean section

肠内营养开始时间对极低出生体重儿消化功能及生长速度的影响

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中国当代儿科杂志 2014年第8期16卷 814-819页

作者：于新颖范玲中国医科大学附属盛京医院新生儿科辽宁沈阳110004

目的探讨极低出生体重儿（VLBWI）适宜的肠内营养开始时间，观察不同肠内营养开始时间对VLBWI消化功能、生长速度及院内感染率的影响。方法选择NICU病区2012年2。12月人院的全部VLBWI，根据肠内营养开始时间，将其分为3组，即≤3d组（11... 详细信息

目的探讨极低出生体重儿（VLBWI）适宜的肠内营养开始时间，观察不同肠内营养开始时间对VLBWI消化功能、生长速度及院内感染率的影响。方法选择NICU病区2012年2。12月人院的全部VLBWI，根据肠内营养开始时间，将其分为3组，即≤3d组（116例）、4。6d组（36例）、≥7d组（26例）。分析不同肠内营养开始时间对消化功能、生长速度及院内感染率等的影响。结果≤3d组生后1周奶量明显高于另2组，≤3d组及4—6d组生后2周、3周奶量明显高于≥7d组。3组生长速度指标比较差异无统计学意义。≤3d组中心静脉置管时间明显短于另外2组，≥7d组达全肠内营养的时间明显长于另外2组。≤3d组院内感染率（13．8％）明显低于≥7d组（46．2％）。结论肠内营养开始时间对VLBWI生长速度无影响，但早期开始肠内营养能促进其胃肠功能成熟，利于奶量增长，能更快达到全肠内营养，缩短中心静脉置管时间，降低院内感染率。

关键词：肠内营养开始时间消化功能生长速度院内感染极低出生体重儿