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婴幼儿配方奶粉中酪蛋白磷酸肽2种检测方法的比较

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食品安全质量检测学报 2018年第19期9卷 5212-5217页

作者：胡蓓赖世云张京顺蒋易蓉任一平浙江工业大学化工学院杭州310014 杭州帕匹德科技有限公司杭州310000 浙江省疾病预防控制中心杭州310051 浙江大学生物系统工程与食品科学学院杭州310058 浙江清华长三角研究院嘉兴314006

目的比较婴幼儿配方奶粉中酪蛋白磷酸肽(casein phosphopeptides,CPPs)的2种主要检测方法。方法分别采用高效液相色谱法(high performance liquid chromatography,HPLC)和高效液相色谱-串联质谱法(high performance liquid chromatography-tandem mass spectrometry, HPLC-MS/MS)检测婴幼儿配方奶粉中酪蛋白磷酸肽的含量。结果 HPLC操作简便,检出限为7.5mg/100g,日内精密度≤2.7%,满足婴幼儿配方奶粉中酪蛋白磷酸肽的检测要求;而HPLC-MS/MS检出限为1mg/100 g,日内精密度≤8.8%,较HPLC具有更好的灵敏度。结论 HPLC高效准确,实验操作简单,适合于CPPs含量较高样品的检测分析;HPLC-MS/MS灵敏度高、特异性强,适用于CPPs含量较低样品的检测。

关键词：酪蛋白磷酸肽高效液相色谱法高效液相色谱-串联质谱法配方奶粉

Microstructural homogeneity and mechanical behavior of a selective laser melted Ti-35Nb alloy produced from an elemental powder mixture

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Journal of Materials Science & Technology 2021年第2期61卷 221-233页

作者： Jincheng Wang Yujing Liu Chirag Dhirajlal Rabadia shun-Xing Liang Timothy Barry Sercombe Lai-Chang zhang School of Engineering Edith Cowan University270Joondalup DriveJoondalupPerthWA 6027Australia School of Engineering M050The University of Western Australia35 Stirling HighwayCrawleyPerthWA 6009Australia

Although using elemental powder mixtures may provide broad alloy selection at low cost for selective laser melting(SLM), there is still a concern on the resultant microstructural and chemical homogeneity of the produced parts. Hence, this work investigates the microstructure and mechanical properties of a SLM-produced Ti-35 Nb composite(in wt%) using elemental powder. The microstructural characteristics including ? phase, undissolved Nb particles and chemical homogeneity were detailed *** revealed the presence of relatively soft undissolved Nb particles and weak interface bonding around Nb-rich regions in as-SLMed samples. Solid-solution treatment can not only improve chemical homogeneity but also enhance bonding through grain boundary strengthening, resulting in43 % increase in tensile elongation for the heat-treated Ti-35 Nb compared to the as-SLMed counterpart. The analyses of tensile fractures and shear bands further confirmed the correlation between the different phases and the ductility of Ti-35 Nb. In particular, the weak bonding between undissolved Nb and the matrix in the as-SLMed sample reduces its ductility while the ? grains in solid-solution treated Ti-Nb alloy can induce a relatively stable plastic flow therefore better ductility. This work sheds insight into the understanding of homogenization of microstructure and phases of SLM-produced alloys from an elemental powder mixture.

关键词： Titanium-niobium Selective laser melting Microstructure Nanoindentation Mechanical behavior

经皮穴位电刺激联合耳穴压豆治疗妇科腹部术后胃肠功能障碍的临床观察

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广州中医药大学学报 2021年第9期38卷 1893-1898页

作者：李晓瑜张永顺管莉文石志敏杜伟武文印唐山市中医医院河北唐山063000 乐亭县中医医院河北乐亭063600 乐亭县妇幼保健院河北乐亭063600

【目的】观察经皮穴位电刺激联合耳穴压豆治疗妇科腹部术后胃肠功能障碍患者的临床疗效。【方法】将70例妇科腹部术后胃肠功能紊乱患者随机分为观察组和对照组,每组各35例。对照组给予马来酸曲美布汀口服治疗,观察组给予经皮穴位电刺激... 详细信息

【目的】观察经皮穴位电刺激联合耳穴压豆治疗妇科腹部术后胃肠功能障碍患者的临床疗效。【方法】将70例妇科腹部术后胃肠功能紊乱患者随机分为观察组和对照组,每组各35例。对照组给予马来酸曲美布汀口服治疗,观察组给予经皮穴位电刺激联合耳穴压豆治疗。疗程为7 d。治疗7 d后,评价2组的临床疗效,比较2组患者术后首次肠鸣音、首次排气与排便时间的情况,观察2组患者治疗前后主要症状、体征评分的变化情况,以及2组患者治疗前后血清二胺氧化酶(DAO)、D-乳酸的水平的变化情况。【结果】(1)研究过程中,观察组失访3例,对照组失访4例。最终观察组32例、对照组31例纳入疗效统计。(2)治疗后,与对照组比较,观察组在改善术后肠鸣音恢复、首次排气和排便时间方面均明显优于对照组,差异有统计学意义(P<0.05)。(3)治疗后,2组患者的主要症状、体征评分均明显改善(P<0.05),且观察组在改善患者主要症状、体征评分方面明显优于对照组,差异均有统计学意义(P<0.05)。(4)治疗后,2组患者的血清DAO、D-乳酸水平均明显改善(P<0.05),且观察组在改善血清DAO、D-乳酸水平方面明显优于对照组,差异均有统计学意义(P<0.05)。(5)观察组总有效率为90.63%(29/32),对照组为74.19%(23/31)。观察组疗效优于对照组,差异有统计学意义(P<0.05)。【结论】经皮穴位电刺激联合耳穴压豆治疗妇科腹部术后胃肠功能障碍,能快速促进腹部术后患者胃肠功能的恢复,改善患者的症状、体征及肠黏膜屏障功能指标,疗效显著。

关键词：经皮穴位电刺激耳穴压豆马来酸曲美布汀胃肠道功能障碍妇科腹部术后临床观察

黄土丘陵沟壑区1∶1万及1∶5万比例尺DEM地形信息容量对比

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水土保持通报 2001年第2期21卷 34-36页

作者：汤国安陈楠刘咏梅张友顺陈正江中科院水利部水土保持研究所陕西杨凌712100 西北大学城市与资源学系陕西西安710069

黄土丘陵沟壑区地形变化异常复杂 ,1∶5万地形图对原始 1∶1万地形图等高线形态综合、取舍程度很大 ,这些都在不同程度上影响了地形分析结果的准确性。以高精度的 1∶1万比例尺DEM为校准值 ,运用 1∶1万及 1∶5万比例尺DEM叠合比较分析... 详细信息

黄土丘陵沟壑区地形变化异常复杂 ,1∶5万地形图对原始 1∶1万地形图等高线形态综合、取舍程度很大 ,这些都在不同程度上影响了地形分析结果的准确性。以高精度的 1∶1万比例尺DEM为校准值 ,运用 1∶1万及 1∶5万比例尺DEM叠合比较分析的方法 ,研究 1∶5万DEM的地形信息容量及提取不同地形要素的精度。试验结果表明 ,在黄土丘陵区 ,与 1∶1万DEM相比 ,1∶5万DEM在所提取的地面坡度、地面曲率、沟壑量等地形定量指标方面均都存在着较大的误差。

关键词：数字地形模型比例尺对比误差地形信息容量

Regulating the formation ability and mechanical properties of high-entropy transition metal carbides by carbon stoichiometry

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Journal of Materials Science & Technology 2022年第26期121卷 181-189页

作者： Juntao Song Guiqing Chen Huimin Xiang Fuzhi Dai shun Dong Wenbo Han Xinghong zhang Yanchun Zhou Science and Technology on Advanced Composite in Special Environments Laboratory Harbin Institute of TechnologyHarbin150080China Science and Technology on Advanced Functional Composite Laboratory Aerospace Research Institute of Materials&Processing TechnologyBeijing100076China

Tremendous efforts have been dedicated to promote the formation ability of high-entropy transition metal ***,the majority of methods for the synthesis of high-entropy transition metal carbides still face the challenges of high temperature,low efficiency,additional longtime post-treatment and uncontrollable *** cope with these challenges,high-entropy transition metal carbides with regulatable carbon stoichiometry(HE TMC)were designed and synthesized,achieving improved ability for single phase solid solutions formation,promoting of sintering and controllable mechanical *** typical composition series,i.e.,easily synthesized(ZrHfTaNb)C(ZHTNC)and difficultly synthesized(Zr_(0.25)Hf_(0.25)Ta_(0.25)Ti_(0.25))C(ZHTTC)are selected to demonstrate the promoting formation ability of single phase solid solutions from carbon stoichiometry *** phase high-entropy ZHTTC,which has been proven difficult in forming a single phase solid solution,can be prepared with the decrease of C/TM ratio under 2000℃;while the high-entropy ZHTNC,which has been proven easy in forming a single phase solid solution,can be synthesized at lower temperatures with the decrease of C/TM *** synergistic effect of entropy stabilization and reduced chemical bond strength gaining from carbon stoichiometry deviations is responsible for the formation of single phase solid solutions and the promoted sintering of HE *** example,the relative density of bulk(ZrHfTaNb)C(SPS-ZHTNC)increases from 90.98%to 94.25%with decreasing the C/TM atomic ratio from 0.9 to *** importantly,the room temperature flexural strength,fracture toughness and brittleness index of SPS-ZHTNCcan be tuned in the range of 384 MPa–419 MPa,4.41 MPam–4.73 MPamand 3.679μm–4.083μm,***,the HE TMCprepared by adjusting the ratio of carbon to refractory transition metal oxides have great potential for achieving low temperature synthesis,promoted sintering and tunable properties.

关键词： Carbon stoichiometry High-entropy ceramics Transition metal carbide Low temperature synthesis Tunable mechanical properties

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多粒子系统的高能集团散射理论

高能物理与核物理 1982年第1期 55-63页

作者：李扬国张禹顺王潍潍阮图南中国科学院高能物理研究所中国科学院理论物理研究所中国科学技术大学

本文以Glauber散射理论为框架,把多粒子系统分为“价”粒子团和“海”粒子团,从而把一个很复杂的多粒子系统的多次散射振幅分解为“海”-“海”,“海”-“价”、“价”-“价”散射振幅。为了方便,我们对每一种散射振幅,用一种有效的近... 详细信息

本文以Glauber散射理论为框架,把多粒子系统分为“价”粒子团和“海”粒子团,从而把一个很复杂的多粒子系统的多次散射振幅分解为“海”-“海”,“海”-“价”、“价”-“价”散射振幅。为了方便,我们对每一种散射振幅,用一种有效的近似方法处理。最后得到物理概念清楚、计算上方便的“海”-“海”、“海”-“价”、“价”-“价”的S矩阵。

关键词：多粒子系统核物理简称散射振幅矩阵元散射理论

One-step preparation of porous aminated-silica nanoparticles and their antibacterial drug delivery applications

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Journal of Materials Science & Technology 2020年第15期47卷 139-146页

作者： Yongren Wu shun Chen Yang Liu Zhiwei Lu Shaokun Song Yang zhang Chuanxi Xiong Lijie Dong Center for Smart Materials and Devices State Key Laboratory of Advanced Technology for Materials Synthesis and ProcessingWuhan University of TechnologyWuhan430070China

Porous functionalized silica nanoparticles have attracted the interest of researchers as they are excellent carriers for antibacterial drug delivery *** this work,porous aminated-silica nanoparticles(SiO2-NH2 NPs) were prepared via one-step approach through the ammonia-catalyzed hydrolysis of tetraethylorthosilicate(TEOS) and(3-aminopropyl) triethoxysilane(APTES) in a mixed water-ethanol *** obtained SiO2-NH2 NPs displayed a spherical morphology and relatively uniform size distribution,while the morphology and structure of SiO2-NH2 NPs were mainly determined by the order of the reagents added and the pH value of the *** characterization,the results showed that there were a large number of-NH2 groups on the surface of porous SiO2-NH2 NPs and that the porous SiO2-NH2 NPs had a large surface area of 476 m2 g-1 with an average pore width of 4.3 *** an absorbing-releasing experiment and bacterial test,those SiO2-NH2 NPs were found to exhibit efficient absorption and release of drugs as well as a pH-de pendent release pattern of epirubicin-loaded SiO2-NH2 ***,SiO2-NH2@capsaicin NPs exhibited antibacterial *** porous SiO2-NH2 NPs could be a candidate for drug delivery for antibacterial applications owing to their tailored porous structure and high surface area.

关键词： Porous aminated-silica nanoparticles Surface area Drug delivery Antibacterial property

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对称群S4的正交单位

高能物理与核物理 1982年第5期 588-594页

作者：王如琳潘辑智张禹顺王潍潍中国科学院高能物理研究所中国科学院理论物理研究所

四个粒子对称群S4有24个群元素,利用替代分析得到该群的酉表示,从而得出十个正交单位。

关键词：对称群王如置换群 S4 正交矩阵

2004年深圳市6区居民行为危险因素电话调查分析

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疾病控制杂志 2005年第6期9卷 561-565页

作者：牟瑾张顺祥马汉武张欣谢旭王昕张小岚李锦王敬忠吕秋莹深圳市疾病预防控制中心广东深圳518020 深圳市卫生监督所广东深圳518020

目的初步建立以随机电话拨号和计算机辅助电话调查为基础的行为危险因素监测系统,并对深圳市成年人疾病和伤害相关的行为危险因素进行调查和分析。方法采用ITACATI软件设计和修改调查问卷,以Mitofsky-Waksberg法进行两阶段抽样,获得电... 详细信息

目的初步建立以随机电话拨号和计算机辅助电话调查为基础的行为危险因素监测系统,并对深圳市成年人疾病和伤害相关的行为危险因素进行调查和分析。方法采用ITACATI软件设计和修改调查问卷,以Mitofsky-Waksberg法进行两阶段抽样,获得电话头号并随机拨号,调查18岁以上深圳居民疾病相关行为危险因素和传染病防治知识。结果本次调查共产生1 180个号码,有效电话459个,有效电话的应答率为88.89%。常参加体育活动者自评健康状况较好,过去1月无疾病的天数较少;安全套使用率为34.8%,使用率随年龄增加而上升;既往和当前吸烟者共占31.9%,男性饮酒率为63.8%,女性为18.3%。调查发现市民自报高血压患病率6.9%。结论将电话调查用于行为危险因素监测是一个效率较高的可行的技术方法,应在今后的公共卫生实践中深入研究,进一步促进监测数据与疾病控制和健康促进实践相结合。

关键词：行为危险因素电话采访