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Journal of Environmental Sciences 2013年第11期25卷 2281-2290页

作者： Ang Li Rui Cai Di Cui Tian qiu Changlong Pang Jixian Yang Fang Ma Nanqi Ren State Key Laboratory of Urban Water Resource and Environment Harbin Institute of Technology National Supervision and Inspection Center of Environmental Protection Equipment Quality Yixing Urban Supervision andInspection Administration of Product Quality

Carbamazepine is frequently detected in waters and hardly eliminated during conventional wastewater treatment processes due to its complicated chemical structure and resistance to biodegradation. A carbamazepine-degrading bacterium named CBZ-4 was isolated at a low temperature （10℃） from activated sludge in a municipal wastewater treatment plant. Strain CBZ-4, which can use carbamazepine as its sole source of carbon and energy, was identified as Pseudomonas sp. by the 16S rRNA gene sequence. The composition and percentage of fatty acids, which can reveal the cold-adaptation mechanism of strain CBZ-4, were determined. Strain CBZ-4 can effectively degrade carbamazepine at optimal conditions： pH 7.0, 10℃, 150 r/min rotation speed, and 13% inoculation volume. The average removal rate of carbamazepine was 46.6% after 144 hr of incubation. The biodegradation kinetics of carbamazepine by CBZ-4 was fitted via the Monod model. Vmax and Ks were found to be 0.0094 hr^-1 and 32.5 mg/L, respectively.

关键词： carbamazepine low temperatures biodegradation kinetics Pseudomonas sp.

Heat Transfer and Its Effect on Solidification in Combined Mould

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Journal of Iron and Steel Research International 2005年第6期12卷 20-22,36页

作者： qiu Sheng-tao TAO Hong-biao TANG Hong-wei ZHANG Hui ZHAO Pei Central Iron and Steel Research Institute Beijing 100081 China

The nucleation can be enhanced by decreasing the superheat of molten steel, thus reducing temperature gradient on the solidification front can retard the growth of columnar crystals and enlarge the equiaxed zone in continuous casting strand. The billets with equiaxed zone more than 90% were cast with a combined mould and the heat flux was measured. The heat transfer of the combined mould and traditional mould was compared. The resuits show that under same casting conditions, the temperature gradient on the solidification front in the combined mould is smaller than that in traditional mould at a distance within 0-150 mm from the meniscus.

关键词： combined mould heat transfer temperature gradient equiaxed zone

Improvements of heat resistance and adhesive property of condensed poly-nuclear aromatic resin via epoxy resin modification

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Petroleum Science 2014年第4期11卷 578-583页

作者： Wu Mingbo Wang Yuwei Jiang Wei Li Shibin Sun Qiqian Zheng Jingtang qiu Jieshan State Key Laboratory of Heavy Oil Processing China University of Petroleum Carbon Research Laboratory State Key Lab of Fine Chemicals School of Chemical Engineering Dalian University of Technology

A bisphenol epoxy resin was used as modifier to increase the heat resistance of condensed poly-nuclear aromatic （COPNA） resin. The basic properties of COPNA resin and modified resin were characterized by Fourier transform infrared spectroscopy （FT-IR）, nuclear magnetic resonance spectroscopy （1H-NMR）, vapor pressure osmometry （VPO） and elemental analysis （EA）. Average structural parameters of resins were calculated by the improved Brown-Ladner method, and heat resistance of resins was tested by thermogravimetric analysis （TGA）. The chemical structure, mechanical properties and heat resistivity of the resin/graphite composites prepared with different resins were compared. The results show that the adhesive property and heat resistance of COPNA resin can be remarkably improved by addition of 5 wt.% epoxy resin. The reason is that the reactions between epoxy groups of epoxy resin and hydroxyl groups of COPNA resin improve the heat resistance and adhesive property of COPNA resin. Electric motor brushes with good mechanical properties and low electrical resistivity were successfully prepared by using the modified resin as binder.

关键词： COPNA resin modification epoxy resin heat resistance mechanical property

Strongly screened electron capture rates of chromium isotopes in presupernova evolution

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Research in Astronomy and Astrophysics 2017年第10期17卷 91-96页

作者： Jing-Jing Liu qiu-He Peng Liang-Huan Hao Xiao-Ping Kang Dong-Mei Liu College of Marine Science and Technology Hainan Tropical Ocean University Department of Astronomy Nanjing University

Taking into account the effect of electron screening on electron energy and electron capture threshold energy, by using the method of Shell-Model Monte Carlo and random phase approximation theory, we investigate the capture rates of chromium isotopes with strong electron screening according to the linear response theory screening model. Strong screening rates can decrease by about 40.43% （e.g., for 6Cr at T9 = 3.44, Ye = 0.43）. Our conclusions may be helpful to researches on supernova explosions and related numerical simulation methods.

关键词： nuclear reactions -- electron capture -- supernovae

Primary effect of dual growing rod technique for the treatment of severe scoliosis in young children

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Chinese Medical Journal 2010年第2期123卷 151-155页

作者： LI Qi-yi ZHANG Jian-guo qiu Gui-xing WANG yi-peng SHEN Jian-xiong ZHAO Yu LI Shu-gang YU Bin WANG Xi WENG Xi-sheng Department of Orthopedic Surgery Peking Union Medical College Hospital Peking Union Medical College Beijing 100730 China

Background Treatment of rapidly progressing scoliosis in young children is a challenge for spine surgeons. Some surgeons had begun to use dual growing rod technique for treatment of rapidly progressing scoliosis in young children and had achieved acceptable results. The aim of this study was to determine the primary results and complications of this new technique in China. Methods Eleven children suffering from rapidly progressing scoliosis were treated with dual growing rod technique between November 2004 and March 2009 at Peking Union Medical College Hospital （PUMCH）. There were 10 females and 1 male in the group with Risser sign of 0 grade. The mean age at initial surgery was 6.1 years （range, 2.1-10.9 years）. Ten patients were diagnosed as congenital scoliosis and 1 patient neuromuscular scoliosis. All the patients had 1-4 lengthening procedures （mean, 1.8 procedures） after the initial surgeries. The radiographic results of all the patients were investigated. Results The coronal Cobb angle of scoliosis improved from （67.64±11.43）% to （34.64±8.26）% after initial surgery with the correction rate observed at （47.15±16.48）%. The coronal trunk shift improved from （2.00±1.73） cm to （1.49±1.31） cm after initial surgery. The T1-S1 height increased from （25.47±6.16） cm to （28.84±5.69） cm after initial surgery. The coronal Cobb angle of scoliosis was （36.82±11.76）% and the coronal trunk shift was （1.11±1.29） cm after the most recent lengthening procedure with the most recent correction rate observed at （44.73±19.43）%. The T1-S1 height was （31.29±4.50） cm after the most recent lengthening procedure with an average T1-S1 length increase of 1.6 （range, 1.0-2.7） cm per year during the lengthening period. The sagittal balance was maintained. Five of the total patients （45.5%） had complications including： hook displacement, pedical screw loosening, and broken rod. We performed revision surgeries with simultaneous lengthening procedures in all 5 cases with satisfactory results.

关键词： scoliosis growing rods operation

上皮钙黏蛋白及其复合体的表达与垂体腺瘤侵袭性的相关性

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中华耳鼻咽喉头颈外科杂志 2006年第6期41卷 433-436页

作者：曲秋懿张秋航王星宇首都医科大学宣武医院耳鼻咽喉头颈外科北京100053

目的探讨上皮型钙黏蛋白(E-cadherin,E-cad)及其与连环蛋白复合体(cadherincatenincomplex,CCC)的表达与垂体腺瘤侵袭性的关系。方法垂体腺瘤78例,按Cottier等提出的鞍区MRI影像学判定标准将其分为侵袭性垂体腺瘤和非侵袭性垂体腺瘤。... 详细信息

目的探讨上皮型钙黏蛋白(E-cadherin,E-cad)及其与连环蛋白复合体(cadherincatenincomplex,CCC)的表达与垂体腺瘤侵袭性的关系。方法垂体腺瘤78例,按Cottier等提出的鞍区MRI影像学判定标准将其分为侵袭性垂体腺瘤和非侵袭性垂体腺瘤。其中侵袭性垂体腺瘤44例,非侵袭性垂体腺瘤34例。免疫组织化学SP法检测E-cad及其复合体在侵袭性垂体腺瘤和非侵袭性垂体腺瘤中的表达。分析E-cad及其复合体的表达与垂体腺瘤激素分泌、是否伴有瘤卒中、坏死、囊性变及肿瘤大小等生物学行为的关系。结果44例侵袭性垂体腺瘤中30例(68·2%)表现为E-cad、α-cat和β-cat一致性低表达,14例(31·8%)表现为E-cad、α-cat和β-cat高、低表达特征无一致性。E-cad、α-cat在侵袭性垂体腺瘤和非侵袭性垂体腺瘤之间的表达差异有统计学意义(χ2=13·969,P0·05);E-cad、α-cat在大腺瘤组较微腺瘤组表达低,两组之间差异有统计学意义(χ2=5·038,P<0·05)。E-cad在无功能垂体腺瘤较激素分泌性垂体腺瘤表达低,两组之间差异有统计学意义(χ2=4·614,P<0·05)。β-cat在伴有瘤卒中、坏死、囊性变组较不伴有组表达低,两组之间差异有统计学意义(χ2=6·701,P<0·05)。结论E-cad及其复合体的低表达或表达缺失与垂体腺瘤的侵袭性有关。

关键词：垂体肿瘤钙黏着糖蛋白类肿瘤浸润

Saponins isolated from Schizocapsa plantaginea inhibit human hepatocellular carcinoma cell growth in vivo and in vitro via mitogen-activated protein kinase signaling

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Chinese Journal of Natural Medicines 2018年第1期16卷 29-40页

作者： SUN Yue-Wen qiu Han-Chen OU Ming-Chun CHEN Run-Li LIANG Gang College of Pharmacy Guangxi Medical University

The underground cane of Schizocapsa plantaginea(Hance) has long been used by Chinese ethnic minority as a constituent of anti-cancer formulae. Saponins are abundant secondary metabolic products located in the underground cane of this plant. The potential therapeutic effects of total saponins isolated from Schizocapsa plantaginea(Hance)(SSPH) on human hepatocellular carcinoma(HCC) were tested in vitro in human liver cancer cell lines, SMMC-7721 and Bel-7404. Apoptosis and cell cycle arrest were determined using flow cytometry, caspase activation was determined by ELISA, and PARP, cleaved PARP, mitogen-activated protein kinase(MAPK) expression and phosphorylation were measured using Western blotting analysis. In vivo anti-HCC effects of SSPH were verified in nude mouse xenograft model. SSPH exerted markedly inhibitory effect on HCC cell proliferation in time-and concentration-dependent manner. Moreover, SSPH significantly induced apoptosis through caspase-dependent signaling and arrested cell cycle at G2/M phase. These anti-proliferation effects of SSPH were associated with up-regulated phosphorylation of extracellular signal-regulated kinase-1/2(Erk1/2) and c-jun-NH2-kinase-1/2(JNK1/2) and reduced phosphorylation of p38 MAPK. Furthermore, inhibitors of ERK, UO126, and JNK, SP600125 inhibited the anti-proliferation effects by SSPH, suggesting that Erk and JNK were the effector molecules in SSPH induced anti-proliferative action. During in vivo experiments, SSPH was found to inhibit xenograft tumor growth in nude mice, with a similar mechanism in vitro. Our study confirmed that SSPH exerted antagonistic effects on human liver cancer cells both in vitro and in vivo. Molecular mechanisms underlying SSPH action might be closely associated with MAPK signaling pathways. These results indicated that SSPH has potential therapeutic effects on HCC.

关键词： Saponins Cancer Liver MAPK Schizocapsa plantaginea

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新型墙体材料冻融循环寿命时变可靠性

中南大学学报（自然科学版） 2011年第11期42卷 3342-3346页

作者：郑怡李莉许嘉龙由世宽回志峰邱连强辽宁省建筑材料科学研究所辽宁沈阳110032 大连理工大学土木水利学院辽宁大连116023 武汉理工大学材料科学与工程学院湖北武汉430070 沈阳建筑大学材料学院辽宁沈阳110168

通过对6种新型墙体材料和烧结普通砖在不同冻融循环次数(0,25,50和75次)下的试验,研究新型墙体材料的质量损失率、强度损失率与循环次数的关系,结合新型墙体材料冻融损伤失效过程,建立新型墙体材料的冻融损伤时变可靠度计算模型。研究... 详细信息

通过对6种新型墙体材料和烧结普通砖在不同冻融循环次数(0,25,50和75次)下的试验,研究新型墙体材料的质量损失率、强度损失率与循环次数的关系,结合新型墙体材料冻融损伤失效过程,建立新型墙体材料的冻融损伤时变可靠度计算模型。研究结果表明:以混凝土实心砖为例,随着时间的推移,混凝土实心砖的冻融循环时变可靠指标逐渐变小,变化趋势呈抛物线型。通过模型可预测新型墙体材料的冻融循环寿命,为新型墙体材料的冻融损伤计算提供依据,为维护部门提供决策依据,降低失效风险。

关键词：新型墙体材料冻融循环寿命时变可靠性

Effects of yttrium and zirconium additions on inclusions and mechanical properties of a reduced activation ferritic/martensitic steel

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Journal of Iron and Steel Research International 2020年第2期27卷 197-207页

作者： Dong-ping Zhan Guo-xing qiu Chang-sheng Li Min Qi Zhou-hua Jiang Hui-shu Zhang School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina State Key Laboratory of Rolling and Automation.Northeastern University Shenyang 110819LiaoningChina School of Metallurgy Engineering Liaoning Institute of Science and TechnologyBenxi 117004.LiaoningChina

The effects of two alloying elements,i.e.,yttrium(Y)and zirconium(Zr),on the inclusion,microstructure,tensile property and impact toughness of reduced activation ferritic/martensitic(RAFM)steel are *** size and number of particles were determined by optical microscopy,and the particle types were examined by scanning electron *** size of?20% and?85% of the inclusions lied in the range of 0.5-1.0μm and 0.5-3.0μm,*** Y-and Y-Zr-containing specimens,the density of the fine inclusions,with a size less than 0.5μm,was found to be 1.06×10^17 and 9.82×10^16 m^-*** specimens were normalized at 1323 K for 30 min and tempered at 923 and 1023 K for 90 min,resulting in the formation of tempered martensite with M23C6 carbides and MX ***-containing RAFM steel tempered at 923 K formed M23C6 carbides and nano-sized carbides with Zr,conferring superior strength balance and impact *** yield strength of alloy reached 695 MPa,and a low ductile-brittle transition temperature of 238 K was maintained.

关键词： 9Cr oxide-dispersion-strengthened steel Inclusion Mechanical property DBTT Yttrium Zirconium

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国家职业教育标准体系及优化研究

中国高教研究 2023年第5期 94-100页

作者：王春燕邱懿北京教育科学研究院北京100031 北京大学北京100871 教育部职业教育与成人教育司教学与质量处北京100816

在我国百年未有之大变局和中华民族伟大复兴的关键时期,职业教育服务中国式现代化建设,体现经济社会和人的全面发展需求,面向供给侧结构性改革为主线的新技术、新业态、新经济培养技术技能人才,加快完善标准体系建设意义重大。分析了影... 详细信息

在我国百年未有之大变局和中华民族伟大复兴的关键时期,职业教育服务中国式现代化建设,体现经济社会和人的全面发展需求,面向供给侧结构性改革为主线的新技术、新业态、新经济培养技术技能人才,加快完善标准体系建设意义重大。分析了影响职业教育的内部和外部标准,基于人才培养周期,构建了条件准入、教学过程和质量评价的国家职业教育标准体系框架,并分析了各部分标准之间的逻辑关系,提出了完善国家职业教育标准框架,建立“横向融通、纵向贯通、内外联通”职业教育标准体系;加强“元标准”的研制水平,规范标准建设技术路径,提升研制人员标准化工作能力;形成具有中国特色的标准建设机制,加强标准管理效能;探索国际职业教育标准认证体系等优化建议,推进国家职业教育标准建设进入从有到优的新阶段,服务科教兴国战略。

关键词：国家职业教育标准体系职业教育标准建设