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  • [专利] 葡甲胺锑酸盐的制备方法

    本发明公开了一种葡甲胺锑酸盐的制备方法,以葡甲胺水溶液滴加 到五氧化二锑胶体溶液当中,葡甲胺和五氧化二锑的质量比为(1∶0.5)~ (1∶3),水相反应,pH通过增减葡甲胺的量进行调节并控制在4.0~9.0, 反应温度30~120℃,反应产物经过精制处理,获得葡甲胺锑酸盐。该 方法所用五氧化二锑胶体溶液系由三氧化二锑与双氧水氧化反应制得, 稳定剂采用葡甲胺,葡甲胺是后步反应的原料,因此,不产生有机废液; 胶体水溶液与葡甲胺水溶液的反应温度控制在30~120℃,比较温和, pH值通过葡甲胺的加入量来控制,无需添加第三种组分,因而反应过程 不会引入其它杂质,也不产生额外的废水和有机废液。

  • [专利] 水飞蓟宾葡甲胺的制备方法

    本发明是一种水飞蓟宾葡甲胺的制备方法,将水飞蓟宾溶于8~12倍的无水乙醇中,将葡甲胺溶于2~3倍的水中;按水飞蓟宾:葡甲胺1∶0.4混合回流2~3小时。减压除去乙醇,干燥得粗品。将粗品溶于适量水中,缓慢加入适量NaCl饱和溶液,过滤得晶体状水飞蓟宾葡甲胺。将晶体状水飞蓟宾葡甲胺溶于乙醇中,再过滤,溶液减压蒸馏去除乙醇,干燥即得精品水飞蓟宾葡甲胺。与原有方法相比,本发明反应更完全,产品质量更稳定,水飞蓟宾葡甲胺纯度达到99%以上,大大高于药品标准。

  • [资讯] 我国塑料齿轮精度标准制订启动 填补国内空白

    >资讯中心我国塑料齿轮精度标准制订启动填补国内空白来源:中国化工报发布时间:2016-6-1716:19:43“从上世纪70年代各地从事注射成型塑料齿轮的生产制造起到现在几十年了我国一直都没有相关的精度标准。对从业人员来说其中的酸甜苦辣真的是不言而喻。”北京工业大学科发院常务副院长、教育部长江学者特聘教授石照耀不止一次地对记者感慨道。这种尴尬让这位为中国在国际齿轮标准制订上赢得话语权的教授深为遗憾尽管应用广泛前景很好我国注射成型塑料齿轮行业也已颇具规模但标准上的空白正严重制约着行业的发展与创新。“特别是目前塑料齿轮模数较小、精度较低且与发达国家的制造水平还存在较大差距这些导致我国仍需从国外进口大量中高档塑料齿轮的被动局面。”石照耀说。但令人高兴的是这一问题即将得到解决。经过三年多的筹备在全国齿轮标准化技术委员会的支持下石照耀牵头联合国内骨干企业于日前在北京成立了《注射成型塑料齿轮精度》国家标准制订工作组并落实了标准的起草分工。而这一步从零到一的跨越将填补我国塑料齿轮行业精度标准几十年的空白。“但这也只是开始接下来我们还将制定塑料齿轮的强度标准等希望通过一系列的标准制定振兴我国的塑料齿轮行业大幅提高行业的质量意识提高企业的竞争力和经济效益以及塑料齿轮行业在国际上的话语权。”该工作组技术顾问、教授级高级工程师欧阳志喜表示。标准空白塑齿行业瓶颈难破自从1935年纤维尼龙研制成功以来高分子合成材料工业迅速发展一种新型材料被应用在齿轮上形成了塑料齿轮。与金属齿轮相比塑料齿轮具有重量轻、惯性小、噪声低、自润滑等优点。其制品采用开模加工生产效率高且成本低经过几十年的发展已广泛应用于汽车电装、家用电器、办公用品、工艺品等各种行业领域。特别是近20年来随着高强度、高耐磨等高性能的工程塑料研发改性成功塑料齿轮的发展应用进一步拓宽它们推动齿轮朝着承受更高负荷、传送更大动力的方向发展在汽车等领域应用的塑料齿轮更有着“以塑代钢”的成功案例。可以说塑料齿轮的迅速发展是世界性趋势。比如深圳海翔铭开发生产的塑齿产品除了满足国内重要用户外还已在多个著名国际汽车品牌的车型上获得使用经济效益显著。“但从整体来看我国的塑料齿轮仍处于中、低档水平高档产品仍需从国外进口特别是在我国塑齿发源地宁波许多塑齿生产厂家的人才、技术和设备没能与时俱进大多数厂家只能生产几分钱一个的塑齿低端产品经济效益低下且难以为继。”欧阳志喜告诉记者。而这与几十年来我国塑料齿轮行业一直都没有相关的精度标准密切相关。记者获悉国内生产的塑齿其精度检测标准长期都是沿用金属齿轮标准的一套理论和精度等级来进行评定但实际上在设计要求、制造方法、应用场所等方面塑料齿轮都与金属齿轮存在较大的差异也因此塑料齿轮的发展一直都深受瓶颈制约。“想要突破这一困境就需要从齿轮产品设计、塑性材料研发、注塑模具设计制造、新型注塑设备与新的注塑工艺研究和齿轮检测与实验等多方面着手研究而这些问题的解决都离不开标准化体系的建立。”石照耀强调说。适合国情塑齿标应有可操作性“首要任务便是制定一部适合我国国情的塑料齿轮标准既具有中国特色又具有可操作。”欧阳志喜表示。20082011年他和石照耀为化学工业出版社特邀撰写《塑料齿轮设计与制造》书稿期间获得了日本JISB1702-32008《有关注塑成型塑料齿轮齿面误差、双齿面啮合误差的定义及其精度容许值》标准——这是全球出现的第一份有关塑齿的精度标准并对该日标的内容和特点有比较详细的了解。那么究竟该如何搭建我国自己的塑料齿轮精度标准架构对此欧阳志喜认为塑料齿轮自身精度标准的制订存在相当的复杂性可以参考日本塑齿标JISB1702-3的做法即塑齿标应以有关金属圆柱齿轮国家标准为基准以注射成型圆柱塑料齿轮的性能、制造方法以及特征作为考察对象来制定我国自己的塑齿标。塑料齿轮与金属齿轮的最大差别就在于齿轮材质和制齿工艺不同。由于在机械性能和热胀冷缩等物理性能上有较大不同导致塑料齿轮的误差特性与金属齿轮有所不同。鉴于此欧阳志喜表示对于塑料齿轮来说采用径向综合测量仪(俗称双啮仪)检测“检测半径”最能反应齿轮的综合精度。但在我国塑齿行业中长期以来利用径向综合测量控制齿轮质量的方法并没有得到有效推广和执行。他认为原因有二一是国产双啮仪软件尚有待开发检测“检测半径”的功能二是国内配套测量齿轮不畅通。“建议对国产双啮仪是否存在检测的不稳定性进行专项论证与攻关建议落实国产测量齿轮进行定点生产单位国产测量齿轮应该坚持价格优惠、保质保量。”欧阳志喜表示。此外对微小塑齿的误差日本塑齿标中没有涉及到应采用何种方法和仪器检测等。众所周知由于模数特小、齿宽小微小模数塑齿既不适合采用齿轮测量中心也不适合采用双啮仪检测。鉴于近年来带激光扫描检测的影像仪已趋成熟欧阳志喜认为作为微型塑齿的检测手段影像仪取代传统的光学投影仪势在必行。至于塑料齿轮的强度与寿命试验由于日标也没有涉及他建议塑齿标对这个问题有所建树即对塑齿的强度与寿命试验的模式进行规范化和标准化争取有所突破。分享到郑重声明本文仅代表作者个人观点与中国化工报社中国石油和化工网无关。其原创性以及文中陈述文字和内容未经本站证实对本文以及其中全部或者部分内容、文字的真实性、完整性、及时性本站不作任何保证或承诺请读者仅作参考并请自行核实相关内容。

  • [期刊] Pulmonary Hypertension Complicating Fibrosing Mediastinitis

    Fibrosing mediastinitis is caused by a proliferation of fibrous tissue in the mediastinum with encasement of mediastinal viscera and compression of mediastinal bronchovascular structures. Pulmonary hypertension (PH) is a severe complication of fibrosing mediastinitis caused by extrinsic compression of the pulmonary arteries and/or veins.We have conducted a retrospective observational study reviewing clinical, functional, hemodynamic, radiological characteristics, and outcome of 27 consecutive cases of PH associated with fibrosing mediastinitis diagnosed between 2003 and 2014 at the French Referral Centre for PH.Fourteen men and 13 women with a median age of 60 years (range 18-84) had PH confirmed on right heart catheterization. The causes of fibrosing mediastinitis were sarcoidosis (n=13), tuberculosis-infection confirmed or suspected (n=9), mediastinal irradiation (n=2), and idiopathic (n=3). Sixteen patients (59%) were in NYHA functional class III and IV. Right heart catheterization confirmed moderate to severe PH with a median mean pulmonary artery pressure of 42 mm Hg (range 27-90) and a median cardiac index of 2.8 L/min/m(2) (range 1.6-4.3). Precapillary PH was found in 22 patients, postcapillary PH in 2, and combined postcapillary and precapillary PH in 3. Severe extrinsic compression of pulmonary arteries (>60% reduction in diameter) was evidenced in 2, 8, and 12 patients at the main, lobar, or segmental levels, respectively. Fourteen patients had at least one severe pulmonary venous compression with associated pleural effusion in 6 of them. PAH therapy was initiated in 7 patients and corticosteroid therapy (0.5-1mg/kg/day) was initiated in 3 patients with sarcoidosis, with 9 other being already on low-dose corticosteroids. At 1-year follow-up, 3 patients had died and among the 21 patients evaluated, 3 deteriorated, 14 were stable, and only 4 patients with sarcoidosis improved (4 receiving corticosteroids and 1 receiving corticosteroids and PAH therapy). Survival was 88%, 73%, and 56% at 1, 3, and 5 years, respectively.We found no clear clinical improvement with the use of specific PAH therapy. Corticosteroid therapy may be associated with clinical improvement, in some patients with fibrosing mediastinitis due to sarcoidosis. Although never performed for this indication, lung transplantation may be proposed in eligible patients with severe PH and fibrosing mediastinitis.

  • [期刊] 莫能霉素中毒致多器官功能障碍4例的护理体会

    莫能霉素属聚醚类抗生素,广泛用于肉鸡、肉牛和肉羊的饲料中,其正式名称叫莫能霉素钠(monensin sodium).也叫瘤胃素、莫能菌酸、莫能菌素、孟宁素、摩能霉素钠等。莫能霉素为白色或类白色结晶,有特殊臭味,干燥失重(60℃真空干燥)〈4%.灰分8%~13%,重金属〈0。0002%,砷〈0.0004%。按干燥品计,每毫克效价不低于800莫能霉素单位。我院自2004年4月1日收冶4例接触莫能霉素所致的职业性化合物中毒性多器官功能障碍综合征病人,经积极治疗和护理.病人已处于恢复期.现将护理体会总结如下。

  • [期刊] Reduction and covalent modification of graphene-oxide by nitrogen in glow discharge plasma

    In this work, we performed plasma treatment of thin layers of graphene oxide samples in various nitrogen containing gases (mainly NH3 and N-2). Experiments were performed in the preparation chamber of the X-ray photoelectron spectrometer, allowing "in situ" characterization of the treated surface. Introduction of nitrogen into the top surface was intensified by applying negative voltage on the sample between 0 and 300 V accelerating the positive plasma ions towards the sample.

  • [期刊] Radiation-Hardened 14T SRAM Bitcell With Speed and Power Optimized for Space Application

    In this paper, a novel radiation-hardened 14-transistor SRAM bitcell with speed and power optimized [radiation-hardened with speed and power optimized (RSP)-14T] for space application is proposed. By circuit-and layout-level optimization design in a 65-nm CMOS technology, the 3-D TCAD mixed-mode simulation results show that the novel structure is provided with increased resilience to single-event upset as well as single-event-multiple-node upsets due to the charge sharing among OFF-transistors. Moreover, the HSPICE simulation results show that the write speed and power consumption of the proposed RSP-14T are improved by similar to 65% and similar to 50%, respectively, compared with those of the radiation hardened design (RHD)-12T memory cell.

  • [期刊] 聚醚类抗生泰莫能霉泰多克隆抗体的制备

    为了探索快速、有效地测定动物源食品中莫能霉素含量的方法,试验对莫能霉素进行修饰,合成半抗原莫能霉素琥珀酸衍生物(MON-HS),再将其与蛋白载体交联制得免疫原与包被抗原,经过多次免疫动物获得抗莫能霉素多克隆抗体,同时对所得抗体的特性进行鉴定与检测.结果表明:在优化之后的最佳试验条件下,用该抗体建立的间接竞争ELISA法最低检出限为0.09 ng/mL,IC50为5 ng/mL.说明试验所制得莫能霉素多克隆抗体具有很高的灵敏性,可以通过对其进一步研究,建立一种检测食品动物中莫能霉素残留的快速、灵敏、有效的方法.

  • [期刊] 莫能菌素对蚯蚓的生态毒理效应

    采用人工土壤法测定了不同浓度莫能菌素对蚯蚓的急性毒性和对蚯蚓生长、生存、繁殖以及超氧化物歧化酶(SOD)、谷胱甘肽-硫转移酶(GSH-S)、腺三磷酸酶(ATPase)、乙酰胆碱酯酶(T-CHE)活性的影响.结果表明,莫能菌素对蚯蚓14 d的LC50为75.883 mg·kg-1;当莫能菌素含量达到50 mg·kg-1时显著影响蚯蚓的生存(P<0.05),死亡率达到20%;当莫能菌素含量达到25 mg·kg-1时显著影响蚯蚓的生长(P<0.05);药物的染毒浓度与对蚯蚓生存和繁殖的抑制存在明显的剂量-效应关系.染毒21 d后,低浓度的兽药莫能菌素就能显著影响蚯蚓体内SOD、GSH-S、ATPase、T-CHE的活性,药物浓度和酶活性间具有明显的剂量-效应关系.莫能菌素对土壤动物蚯蚓显示有毒性作用,对土壤环境具有潜在的生态风险.

  • [期刊] Discharge to Inpatient Care Facility After Vertebroplasty/Kyphoplasty: Incidence, Risk Factors, and Postdischarge Outcomes

    IntroductionVertebral compression fractures are a common clinical occurrence in elderly individuals with osteoporosis. No current evidence exists on risk factors and clinical impact of discharge to inpatient (IP) care facility after vertebral augmentation procedures. Materials and MethodsThe 2012–2014 American College of Surgeons–National Surgical Quality Improvement Program (ACS-NSQIP) database files were queried using Current Procedural Terminology codes for vertebroplasty (22520, 22521, and 22522) and kyphoplasty (22523, 22524, and 22525). Discharge to IP care facility included skilled-care facilities and IP rehabilitation units. A total of 2361 patients were included in the final cohort. ResultsOf 2361 patients, 1962 (83.1%) were discharged home and 399 (16.9%) were discharged to an IP care facility. Multivariate analysis identified age ≥65 years (P 1 day (P< 0.001) to be significant predictors for a discharge to an IP care facility. In addition, discharge to an IP care facility was associated with a significant greater risk of 30-day mortality (P?=?0.001). No significant associations were found with between IP-care discharge destination and any 30-day complication, 30-day readmission, and 30-day reoperation. ConclusionsDischarge to IP care facilities after vertebroplasty/kyphoplasty is associated with a 3.6 times greater odds of mortality as compared with home discharge. Providers can use the risk profile data to better allow preoperative stratification of patients to ensure that discharge location is appropriate to a patient's need to minimize the risk of adverse outcomes.

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