红霉素明胶微球的测定技术分析

目的建立红霉素明胶微球中红霉素含量的测定方法。方法采用高效液相色谱法,色谱柱为DIKMAC18色谱柱（5μm,250mm×4．6mm）,流动相为0．1mol／L磷酸二氢铵（三乙胺调节至pH6．5）乙腈（体积比67：33）,流速1mL／min;检测波长210nm。结果红霉素质量浓度在0．0992-0．4960mg／mL范围内与峰面积呈良好线性关系,r=0．9999;平均回收率为100．1％,RSD=0．95％（n=9）。结论本文方法可用于红霉素明胶微球的含量检测。     

研究HPLC法测定红霉素明胶微球的含量

目的建立红霉素明胶微球中红霉素含量的测定方法。方法采用高效液相色谱法,色谱柱为DIKMA C18色谱柱（5μm,250mm×4．6mm）,流动相为0．1mol／L磷酸二氢铵（三乙胺调节至pH6．5）乙腈（体积比67：33）,流速lmL／min;检测波长210nm。结果红霉素质量浓度在0．0992～0．4960mg／mL范围内与峰面积呈良好线性关系,r=0．9999;平均回收率为100．1％,RSD=0．95％（n=9）。结论本文方法可用于红霉素明胶微球的含量检测。     

UPLC测定黄连中盐酸小檗碱和盐酸巴马汀的含量

建立UPLC测定黄连中盐酸小檗碱和盐酸巴马汀含量的方法。采用ACQUITY UPLC BEH-C18色谱柱(2.1mm×50 mm×1.7μm),以乙腈-0.05mol/L磷酸二氢钾溶液为流动相,梯度洗脱,流速为0.2 mL/min,检测波长为350 nm。结果表明盐酸小檗碱和盐酸巴马汀分别在0.037 2～0.297 6μg/mL,0.008 2～0.065 6μg/mL的浓度范围内均有良好的线性关系(r=0.9999),回收率均大于95%,RSD均小于2%。该方法快速、准确、重现性好,可用于测定黄连中盐酸小檗碱和盐酸巴马汀的含量。     

UPLC同时测定决明子中橙黄决明素、大黄素、大黄酚和大黄素甲醚的含量

建立UPLC同时测定决明子中橙黄决明素、大黄素、大黄酚和大黄素甲醚含量的方法,采用ACQUITY UPLCBEH-C18色谱柱(2.1 mm×50 mm×1.7μm),乙腈和0.1%磷酸水溶液为流动相,采用梯度洗脱,流速为0.6 mL/min,检测波长为284nm。结果表明橙黄决明素、大黄素、大黄酚和大黄素甲醚分别在3.002～30.02μg/mL、2.500～25.00μg/mL、10.430～104.30μg/mL和5.916～59.16μg/mL的浓度范围内均有良好的线性关系(r=0.999 9),回收率均大于95%,RSD均小于2%。该方法快速,准确,重现性好,可用于测定决明子中橙黄决明素、大黄素、大黄酚和大黄素甲醚的含量。     

催化动力学光度法测定镀铬液中的铬(Ⅵ)

在pH=5.7的HAc-NaAc缓冲介质、90℃恒温水浴中,铬(Ⅵ)能显著催化过氧化氢氧化胭脂红的褪色反应.研究了影响催化反应速度的最佳条件,建立了测定铬(Ⅵ)的新方法,铬(Ⅵ)的浓度在0.5～1.5μg/mL范围内符合比耳定律,表观摩尔吸光系数为3.905×103L/mol·cm.该方法的检出限量为0.045μg/mL,此法用于镀铬液中铬(Ⅵ)的测定,结果令人满意.     

HPLC法测定硝酸咪唑的含量

目的:建立测定硝酸咪康唑含量的高效液相色谱(HPLC)法.方法:色谱柱为C18柱(4.6mm×100mm,5μm),流动相为甲醇-乙腈-2%乙酸铵(380:300:320),检测波长为235nm.结果:硝酸咪康唑质量浓度在0.2～1.8mg/mL范围内与峰面积呈良好的线性关系(r=0.9999).结论:HPLC法准确、...     

离子色谱法在饮用水溴酸盐分析中的应用

采用抑制电导离子色谱法(IC)检测饮用水中的痕量溴酸盐.对样品中高浓度的干扰组分氯离子进行了处理,避免其对测定的影响.溴酸盐浓度在5ng/mL～100ng/mL范围内具有良好的线性关系,相关系数为0.9999,方法的定量限为2ng/mL(S/N=10),样品加标回收率大于91.6%.该方法经试验,成功地试用于各种饮用水中溴酸盐含量的测定.     

用萃取光度法测定镀镍液中的微量铜

在pH值为4的条件下,以二乙基氨荒酸铅[Pb(DDTC)2]的氯仿溶液为萃取剂,用一次萃取法与镀镍液中的微量Cu2 进行交换,将Cu(DDTC)2萃取进入有机相,用分光光度法在波长436 nm处测定了镀液中的铜含量.结果表明,Cu(DDTC)2的表观摩尔吸光系数为1.16×104 L/(mol·cm),在0～3.2 μg/mL范围内吸光度与Cu2 浓度呈良好的线性关系,相关系数r=0.999 8,检出限为0.026 μg/mL,应用该方法对镀镍液样品进行测定,测定的相对标准偏差为1.6%,加标回收率为96.7%～101.9%.大量镍离子的存在对铜的测定无干扰.该方法具有较高的灵敏度、准确度与精确度,适宜于镀镍液中微量铜的现场分析.     

示波极谱法快速测定水样中微量镍

在pH9.6的Na2B4O7电解质中,镍和丁二酮肟在-1060mV(vs.SCE)处产生灵敏的络合吸附波,峰电流与镍的浓度在1.0×10-3～25μg/mL范围内呈线性关系,检出限为0.12ng/mL。该方法仪器试剂简单,操作快速简便,用于测定水样中微量镍,结果满意。     

梯度洗脱HPLC法测定利培酮的含量

目的:建立测定利培酮含量的梯度洗脱高效液相色谱(HPLC)法。方法:色谱柱为C18柱(4.6mm×100mm,3μm),流动相A为乙酸铵缓冲液(0.2mol/L,PH6.5)-甲醇-水(100∶150∶750),流动相B为乙酸铵缓冲液(0.2mol/L,PH6.5)-甲醇-水(100∶850∶50),检测波长为275nm,流速1.5ml/min,柱温35℃。结果:利培酮质量浓度在0.5～1.5mg/mL范围内与峰面积呈良好的线性关系(r=0.9998)。结论:梯度洗脱HPLC法测定利培酮的含量,方法准确、专属性强、重现性好,适用于利培酮的含量测定。     

Insertion of triangulated surfaces into a meccano tetrahedral discretization by means of mesh refinement and optimization procedures

In this paper, we present a new method for inserting several triangulated surfaces into an existing tetrahedral mesh generated by the meccano method. The result is a conformal mesh where each inserted surface is approximated by a set of faces of the final tetrahedral mesh. First, the tetrahedral mesh is refined around the inserted surfaces to capture their geometric features. Second, each immersed surface is approximated by a set of faces from the tetrahedral mesh. Third, following a novel approach, the nodes of the approximated surfaces are mapped to the corresponding immersed surface. Fourth, we untangle and smooth the mesh by optimizing a regularized shape distortion measure for tetrahedral elements in which we move all the nodes of the mesh, restricting the movement of the edge and surface nodes along the corresponding entity they belong to. The refining process allows approximating the immersed surface for any initial meccano tetrahedral mesh. Moreover, the proposed projection method avoids computational expensive geometric projections. Finally, the applied simultaneous untangling and smoothing process delivers a high‐quality mesh and ensures that the immersed surfaces are interpolated. Several examples are presented to assess the properties of the proposed method.     

Certification Institutions Expected to Update and Transfer Information on Present Standards

Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.……     

Flow calorimeter for enthalpy increment measurements on condensed gases

A flow calorimeter for enthalpy increment measurements on condensed gases is presented. A better knowledge of the properties of the liquefied natural gas is needed, and therefore a liquid loop has been designed for our flow calorimeter. The fluid loop in the calorimeter is designed in order to avoid the two-phase region, since two phases would give compositional disturbances in the measurements. The avoidance of the two-phase region is made possible by increasing the pressure of the test fluid after the measurement section, then heating the fluid at super-critical pressure past the critical point. Finally, the fluid is throttled to the low-pressure gas state at the inlet condition of the compressor that circulates the fluid. To perform the pressure increase, a new cryogenic pump has been designed. To evaluate the new equipment, measurements were taken on liquid ethane over the temperature range 146–256 K at pressure between 0.9 and 5.1 MPa.     

Refrigerators Enter a New Era of Health Preservation Frestech initiates the establishment of China's first standard for household sterilization refrigerators

On November 30, 2007, the China Association for Standardization (CAS) held a press conference at Beijing Diaoyutai State Guest House. Leaders from the China Household Electric Appliance Research Institute, the China Household Electric Appliance Association, and the China Consumers' Association attended and made speeches.……     

Optimum-Simulation von Ernteprozessen

Zusammenfassung Bei der Gestaltung von Ernteprozessen — beispielsweise des Prozesses Mähdrusch, Körnertransport und -abnahme — als transportverbundene Fließarbeitsverfahren mit mindestens zwei verschiedenen Arbeitsmitteln gibt es einen großen Optimierungsspielraum. Solche Prozesse sind mehrstufige Bedienungsprozesse mit gemischter Anordnung der Bedienungseinrichtungen. Außerdem besitzen sie stark ausgeprägte räumliche Aspekte. Es wird vor allem gezeigt, welche Merkmale solcher Prozesse in Simulationsmodellen abgebildet sein müssen, welche Zielgrößen in Abhängigkeit von welchen Einflußgrößen unter Berücksichtigung welcher Prozeßbedingungen ermittelt werden sollten und wie der Bewertungsprozeß zur Ermittlung der gewünschten Informationen gestaltet werden muß.     

A study of centrifugal cast high boron high speed steel

In the present study a high‐boron high speed steel (HSS) roll material was designed. Many expensive alloy elements have been substituted by cheap boron alloy, and high‐boron high speed steel roll has been manufactured by centrifugal casting method. The microstructures, mechanical properties and wear resistance of centrifugal casting high‐boron high speed steel roll have been investigated by optical microscopy (OM), scanning electron microscopy (SEM), and X‐ray diffraction (XRD) analysis, hardness test, impact test and wear test. The results indicated that the solidification microstructures of high‐boron high speed steel roll consisted of M₂(B,C), (W,Mo)₂(B,C), M₃(B,C), M₂₃(B,C)₆ type borocarbides and martensite, a small amount of retained austenite. Borocarbides were continuously distributed over the grain boundary. After quenching from 1050 °C, local broken network appeared in partial borocarbides, and fine secondary borocarbide precipitated from the matrix. After tempering from 525 °C, the amount of precipitated borocarbide increased significantly. After heat treatment, the hardness of high‐boron high speed steel roll excelled 60 HRC, and its impact toughness excelled 8.0 J/cm². The single groove steel rolling amount of high‐boron high speed steel rolls increases by 500% than that of bainite cast iron roll, when the rolls are used in K₁ mill housing of bar mill.     

Brainstorming for ISO Strategy 2016-2020

正Responding to ISO’s appeal for survey for the to-be-developed ISO Strategy Plan for 2016-2020,SAC hosted a special workshop over the needs and comments of various fi elds on June 8 in Beijing.The workshop was attended by ISO President-elect and Ansteel General Manager Zhang Xiaogang,SAC Vice-Administrator Yu Xinli,and 30 experts from     

CNAS Passes APLAC's PTP Review

正The review group of Asia Pacific Laboratory Accreditation Cooperation(APLAC)carried out a 4-day peer review of the proficiency testing provider(PTP)for China National Accreditation Service for Conformity Assessment(CNAS)from July 28 to 31,2014.CNAS passed the PTP review with excellent performance.Two senior peer reviewers of APLAC made a comprehensive,rigorous and detailed review of CNAS’s PTP accreditation activities,and made the on-spot inspection of the review groups in Shanghai and Shenzhen respectively.     

新闻(英文)

正China and Greece Sign the Standardization Cooperation Agreement Witnessed by Chinese Premier Li Keqiang and Greek Prime Minister Antonis Samaras,AQSIQ Minister Zhi Shuping and ELOT Chairman and Executive Director Angelos Tolkas signed the SAC-ELOT Standardization Cooperation Agreement.The Agreement is one of the critical cooperation documents signed during Li Keqiang’s visit in Greece,encouraging China and Greece to