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Structure,optical,and magnetic properties of Mn-doped ZnO films prepared by sputtering

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International Journal of Minerals,Metallurgy and Materials 2010年第4期17卷 475-480页

作者： li-wei Wang Zheng xu Fu-junZhang Su-ling Zhao li-fang Lu Institute of Optoelectronics Technology Key Laboratory of Luminescence and Optical Information （Ministry of Education of China） Beijing Jiaotong University Beijing100044 China

The microstructural, optical, and magnetic properties and room-temperature photoluminescence （PL） ofMn-doped ZnO thin films were studied. The chemical compositions were examined by energy dispersive X-ray spectroscopy （EDS） and the charge state of Mn ions in the ZnO：Mn films was characterized by X-ray photoelectronic spectrometry （XPS）. From the X-ray diffraction （XRD） data of the samples, it can be found that Mn doping does not change the orientation of ZnO thin films. All the films prepared have a wurtzite structure and grow mainly along the c-axis orientation. The grain size and the residual stress were calculated from the XRD results. The optical transmittance of the film decreases with the increase of manganese content in ZnO. The room-temperature photoluminescence of the films shows that the in- tensity of near band energy （NBE） emission depends strongly on the Mn content. The hysteresis behavior indicates that the films with the Mn content below 9at% are ferromagnetic at room temperature.

关键词： ZnO magnetron sputtering ferromagnetism optical properties photoluminescence

Technology of gas drainage and utilization in Huaibei mining area

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Journal of Coal Science & Engineering(China) 2009年第3期15卷 278-283页

作者： li wei xu Rui Huaibei Mining （Group） Co. Ltd. Huaibei 235000 China

With the characteristics of coal seam geology and gas occurrence,a'ground-underground' integrated gas drainage method was formed,which can relieve gaspressure and increase permeability by mining the protection seams in conditional *** coal seam gas drainage,high gas outburst seam was converted to low gas *** the coal face mining process,safety and high efficient coal mining were realizedby the measure of gas-suction over *** addition to the drainage gas for civil gasand gas power generation,the Huaibei Mining Group has actively carried out research onthe utilization technology of methane drainage by *** the one hand,it can saveprecious energy;on the other hand,it can protect the environment for people's ***2007,the amount of coal mine gas drainage was 120 hm3;the rate of coal mine gasdrainage was 44%.Compared with the year 2002,the amount of coal mine gas drainageincreased by two ***,the utilization rate of gas increased rapidly.

关键词： gas drainage gas utilization Huaibei mining area

A HIGH-SPEED PHOTOGRAPHIC STUDY OF ULTRASONIC CAVITATION NEAR RIGID BOUNDARY

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Journal of Hydrodynamics 2008年第5期20卷 637-644页

作者： BAI li-xin xu wei-lin TIAN Zhong li Nai-wen State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University Chengdu 610065China.

This article investigated an existing steady pattern of collapse and rebound （disintegration and aggregation） of cavitation bubbles near rigid boundary in acoustic field. A deformation process of cavitation bubble was accomplished in two acoustic cycles, namely, a spherical bubble collapsed towards the boundary to its minimum volume and then rebounded and grew into a toroidal bubble （or two individual bubbles） in one acoustic cycle, and the toroidal bubble （or two individual bubbles） collapsed towards the center of ring to its minimum volume, and then rebounded into a spherical bubble in the next acoustic cycle. Inertia force plays a key role in the transition between these two states. The microjet produced during the collapse of spherical bubble and the shock wave produced during the collapse of toroidal bubble （or two individual bubbles） impacts the boundary alternately. A cavitation bubble operating in this pattena can thus be an effective corrosion mechanism of rigid boundary.

关键词： cavity ultrasonic cavitation high-speed photography visualization

Effects of climate change on water resources in Tarim River Basin, Northwest China

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Journal of Environmental Sciences 2007年第4期19卷 488-493页

作者： CHEN Ya-ning li wei-hong xu Chang-chun HAO Xin-ming Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China.

Based on hydrology, temperature, and precipitation data from the past 50 years, the effects of climate change on water resources in Tarim River Basin in Northwest China were investigated. The long-term trends of the hydrological time series were detected using both parametric and nonparametric techniques. The results showed that the increasing tendency of the temperature has a 5% level of significance, and the temperature increased by nearly 1℃ over the past 50 years. The precipitation showed a significant increase in the 1980s and 1990s, and the average annual precipitation exhibited an increasing trend with a magnitude of 6.8 mm per decade. A step change occurred in both the temperature and precipitation time series around 1986. The streamflow from the headwater of the Tarim River exhibited a significant increase during the last 20 years. The increase in temperature, precipitation, and streamflow may be attributed to global climate change.

关键词： climate change temperature precipitation streamflow Tarim River

Role of color Doppler flow imaging in applicable anatomy of spleen vessels

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World Journal of Gastroenterology 2009年第5期15卷 607-611页

作者： wei-li xu Suo-lin li Yan Wang Meng li Ai-Guo Niu Department of Pediatric Surgery the Second Hospital of Hebei Medical University Shijiazhuang 050000 Hebei Province China Department of Ultrasound the Second Hospital of Hebei Medical University Shijiazhuang 050000 Hebei Province China

AIM： To explore the role of color Doppler flow imaging （CDFI） in visualization of spleen vessels and to define its value for spleen micro-invasive operation. METHODS： A total of 36 patients requiring laparoscopic splenectomy （LS） for various hematopathies and autoimmune diseases were randomly selected from April 2005 to May 2008. Anatomic types of spleen pedicle, adjacent relations between spleen vessels and pancreas, diameters of spleen artery and vein were detected and recorded by preoperative CDFI. Different operative procedures were performed according to different anatomic frameworks. The parameters were recorded by telerecording during LS and compared with those by preoperative CDFI using Chi-square test. RESULTS： Two anatomic types of spleen pedicle and four different adjacent relations between spleen vessels and pancreas were detected by CDFI. The diameters of spleen artery and vein detected by CDFI were 0.46 ± 0.09 cm and 0.85 ± 0.35 cm, respectively. There was no statistical difference between the parameters recorded by CDFI and by telerecording （X^2 = 0.250, 0.677, P 〉 0.05）. LS was successfully performed following the anatomic information provided by preoperative ***： Different anatomic frameworks of spleen vessels can be provided by preoperative CDFI, which instructs micro-invasive operation of spleen and increase the safety of operation.

关键词： Ultrasound, Color Doppler imaging Spleen Anatomy Laparoscopic operation

Effects of nitrogen content on pitting corrosion resistance of non-magnetic drill collar steel

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Journal of Iron and Steel Research International 2020年第12期27卷 1466-1475页

作者： li-wei xu Hua-bing li Huai-bei Zheng Peng-chong Lu Hao Feng Shu-cai Zhang wei-chao Jiao Zhou-hua Jiang School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina State Key Laboratory of Metal Material for Marine Equipment and Application Anshan 114002LiaoningChina

High-nitrogen (N) austenitic stainless steel (Cr-Mn-N series) is commonly used for non-magnetic drill collars, which exhibits excellent mechanical properties and corrosion resistance. The effects of N content (0.63 to 0.86 wt.%) on the pitting corrosion behavior of the experimental non-magnetic drill collar steel were investigated using the electrochemical tests and immersion tests. Besides, X-ray photoelectron spectroscopy was used to analyze the constitution of the passive film. The results show that with the enhancement of N content from 0.63 to 0.86 wt.%, the metastable pitting corrosion sensitivity of the tested materials in 3.5 wt.% NaCl solution decreased and the pitting corrosion resistance increased. Meanwhile, the corrosion rate in 6 wt.% FeCl3 solution at 30 ℃ decreased from 10.40 to 4.93 mm/a. On the other hand, nitrogen was concentrated in the form of ammonia (NH4+ and NH3)on the outermost surface of the passive films. The contents of Cr2O3 and Fe2O3 raised in the passive films, together with the content of CrN, at metal/film interface increased as N content increased from 0.63 to 0.86 wt.%, which facilitated protective ability of the passive films, thus contributing to higher pitting corrosion resistance.

关键词： Non-magnetic drill collar Nitrogen Stainless steel Pitting corrosion Passive film

PSD95 Gene Specific siRNAs Attenuate Neuropathic Pain through Modulating Neuron Sensibility and Postsynaptic CaMKIIα Phosphorylation

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Chinese Medical Sciences Journal 2011年第4期26卷 201-207页

作者： Le Shen xu li Wen Chen li xu wei liu xue-rong Yu Yu-guang Huang Department of Anesthesiology Peking Union Medical College Hospital Chinese Academy of Medical Sciences ＆ Peking Union Medical College Beijing 100730 China

Objective To observe the effects of PSD95 gene specific siRNAs on neuropathic pain relief, neuron viability, and postsynaptic calcium/calmodulin-dependent protein kinase IIα (CaMKIIα) phosphorylation in vitro and in vivo. Methods Gene-specific siRNAs of rat PSD95 were synthesized chemically for transfection. Adult male Sprague-Dawley (SD) rats were randomly divided into 3 groups: nave group (n=6), sham group (n=6), and sciatic nerve chronic constriction injury (CCI) group (n=24). The CCI group was further divided into 4 groups (n=6 in each group), which were pretreated with normal saline, transfection vehicle, negative control siRNAs, and PSD95 gene specific siRNAs respectively. All the subgroups received corresponding agents intrathecally for 3 days, started one day before the CCI of sciatic nerve. Both mechanical allodynia and thermal hyperalgesia were measured on post-operative day 3 and 7. PSD95 gene silenced NG108-15 cells were further stimulated by glutamate, with the cell viability and the expression/phosphorylation of CaMKIIα measured by MTT cell proliferation assay and Western blot, respectively. Results The siRNAs decreased PSD95 mRNA level significantly both in vivo and in vitro. Neuropathic pain rats pretreated with PSD95 gene specific siRNAs exhibited significant elevation in the mechanical withdrawal threshold and paw withdrawal thermal latency, without affecting the baseline nociception. PSD95 gene silencing enhanced neuronal tolerance against the glutamate excitotoxicity, meanwhile the phosphorylation of CaMKIIα Thr286 was attenuated. Conclusion Pre-emptive administration of PSD95 gene specific siRNAs may attenuate the central sensitization CaMKIIα-related signaling cascades, leading to the relief of neuropathic pain.

关键词： PSD95 siRNAs neuropathic pain glutamate excitotoxicity calcium/calmodulin- dependent protein kinase IItt

Metachronous contralateral testicular and bilateral adrenal metastasis of chromophobe renal cell carcinoma:a case report and review of the literature

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第5期11卷 386-389页

作者： Hai-yang WU li-wei xu You-yun ZHANG Yan-lan YU Xin-de li Gong-hui li Department of Urology Sir Run Run Shaw Hospital School of Medicine Zhejiang University Hangzhou 310016 China

Chromophobe renal cell carcinoma(ChRCC) metastatic to the testis has not,to the best of our knowledge,been reported in the *** have there been reports of delayed bilateral adrenal metastasis of *** we report a case of metachronous contralateral testicular and bilateral adrenal metastasis of ChRCC in a 70-year-old man who underwent right radical nephrectomy for RCC six years *** was admitted to the hospital because of left intrascrotal enlargement of two-month *** revealed a mass in the upper pole of the left *** tomography(CT) showed irregular masses in the bilateral adrenal *** radical orchiectomy and laparoscopic bilateral adrenalectomy were *** pathologic examination showed metastatic ChRCC in the left testis and bilateral adrenal *** follow-up showed that the patient had survived for at least 56 months without *** case highlights the unique behavior of RCC with an unusual site of metastasis and favorable survival after multiple metastasectomy.

关键词： Renal cell carcinoma(RCC) Testicular metastasis Adrenal metastasis Metastasectomy

The Pig Lhx8 Gene:cDNA Cloning,Bioinformatic Analysis and Expression Level in Tissues and Preimplantation Embryos

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Agricultural Sciences in China 2009年第12期8卷 1503-1510页

作者： FANG wei,li Gui-qiang,li Mei-li,WANG wei and xu Yin-xue College of Animal Science & Technology,Nanjing Agricultural University,Nanjing 210095,P.R.China [a] College of Animal Science & Technology Nanjing Agricultural University Nanjing 210095 P.R. China

Evidence has shown in mouse that Lhx8 is a critical factor for maintenance and differentiation of the oocyte during early oogenesis. In the current paper, attempts were made to clone and characterize a gene encoding Lhx8 from pig. Rapid amplification of cDNA ends （RACE） gave rise to a full-length of Lhx8 which contained 1 681 bp nucleotides, with a complete open reading frame of 885 bp, encoding a 295 amino acid polypeptide. Homology search and sequence multialignment demonstrated that the deduced pig Lhx8 protein sequence shared a high identity with Lhx8 from other mammals, including several highly conservative motifs and amino acids. The phylogenetic tree of the liM superfamily proteins has been constructed to reveal the evolutionary relationship of various species. RT-PCR analysis showed that the Lhx8 gene was expressed in gonad and immunity tissues. In preimplantation embryos, Lhx8 mRNA expression profiling using realtime PCR revealed that its mRNA levels were highest in 4-cell stage embryos and gradually decreased until the blastocyst stage.

关键词： pig LhxS molecular cloning mRNA expression qRT-PCR preimplantation embryos