一种方便的、准确的异养菌测定片

随着人口的迅速增长和工业的蓬勃发展,水源日趋紧张,工业上如何节约用水,利用好循环冷却水,防止水遭受异养菌污染巳成为一大课题。异养菌含量是指所有水中细菌总数,它是衡量水质的一个重要指标,它含量的多少直接反映水的品质好坏。在工业冷却水中,国家标准规定异养菌数应控制在105个/毫升以下。若超过这数值。

石油产品铜片腐蚀测定仪校准方法的探讨

石油产品铜片腐蚀测定仪是根据GB/T 5096-2017国家标准和GB/T 5096-2017国家标准的要求设计制造,主要用于评定航空汽油、航空涡轮燃料、车用汽油、农用拖拉机燃料、洗涤溶剂、煤油馏分燃料和润滑油等石油产品对铜片腐蚀的程度。其准确与否直接影响测试产品的好坏,但目前国家未有可依据的校准规范。本文简述了该测定仪的校准方法,并对主要试验参数进行分析,提出了一种可行性校准方法。

闪烁片测定^(14)C植物干样技术

本文提出了利用塑料闪烁片测定^(14)C 植物干样技术,并同燃烧法进行了相关分析。试验表明:在保证样品测量条件(自吸收和几何条件)相对一致的前提下,用本技术测定^(14)C 植物干样是可行的,且具有许多优点:免去大量闪烁液,制样简便快速,重复性好。

HPLC法测定骨力片中淫羊藿苷的含量

目的:建立反相高效液相色谱法测定骨力片中淫羊藿中淫羊藿苷的含量。方法:采用HPLC,大连日谱利C18(200 mm×4.6 mm,5μm),流动相为乙腈-水(25∶75);流速为0.8 ml/min;柱温为室温;检测波长270 nm。结果:本法平均方法回收率均在99%以上。结论:本法快捷、测量准确,可用于骨力片质量控制。

双波长HPLC法同时测定降脂宁片中4种活性成分的含量

目的：建立HPLC波长切换法同时测定降脂宁片中二苯乙烯苷、橙黄决明素、大黄素、大黄酚4种活性成分的含量。方法：采用Agela C_（18）色谱柱（4.6 mm×250 mm,5μm）,柱温40℃,流动相为乙腈-1 m L/L磷酸水溶液,梯度洗脱,流速1.0 m L/min,检测波长320 nm（0-15 min）、284 nm（15-30 min）。结果：二苯乙烯苷、橙黄决明素、大黄素、大黄酚进样量分别在0.190 9~2.385 9μg（r=0.999 9）、0.042 8~0.535 6μg（r=0.999 9）、0.090 6~1.132 0μg（r=0.999 9）、0.033 1~0.413 8μg（r=0.999 7）范围内线性良好,平均加样回收率（n=6）分别为99.34%、100.39%、98.79%、99.85%,RSD值均〈3%。3批降脂宁片二苯乙烯苷、橙黄决明素、大黄素、大黄酚的含量分别为1.036 0~1.092 8,0.018 2~0.027 0,0.049 5~0.075 7,0.027 6~0.043 8 mg/g。结论：该方法准确、简便,可用于降脂宁片中二苯乙烯苷和蒽醌类成分的含量测定。

乙酰螺旋霉素片含量测定不确定度评定

目的建立并运用抗生素微生物检定法测定乙酰螺旋霉素片含量测定的不确定度评定方法。方法应用测量不确定度评定方法分析检验过程中不确定度的主要来源。结果不确定度的主要来源:(1)供试品的溶解过程带来的不确定度;(2)供试品的稀释过程带来的不确定度;(3)标准品的称量过程带来的不确定度;(4)标准品的溶解过程带来的不确定度;(5)标准品的稀释过程带来的不确定度;(6)微生物检定过程带来的不确定度;(7)结果重复性带来的不确定度。结论运用不确定度评定方法有助于检测人员在检测过程中重点关注关键环节的质量控制,以提高检测工作的质量。

反相高效液相色谱法测定双嘧达莫片的含量

目的建立双嘧达莫片的反相高效液相色谱含量测定方法,更有效地控制药品质量。方法采用Diamonsal C18柱(150mm×4.6mm,5μm),流动相为0.05%磷酸二氢钾-甲醇(20∶80),流速1.5mL.min-1,检测波长为283nm。结果双嘧达莫在6.25～250/μg.mL-1范围内线性关系良好,r=1(n=11),平均回收率为99.17%,RSD为0.49%(n=6)。结论该方法简便、快速、准确。

Development and Validation of an HPLC Method for the Determination of Bupropion Hydrochloride in Tablets

A rapid, accurate and sensitive HPLC method for the determination of bupropion hydrochloride in a new tablet formulation is described. Chromatographic separation of bupropion hydrochloride is achieved using a mobile phase consisting of methanol -0.01 mol·L -1 ammonium dihydrogen phosphate (80:20, v/v, pH 4.8) at a flow rate of 1.0 mL·min -1 on a Hypersil BDS C18 column. Absorbance is monitored at 251 nm where bupropion hydrochloride has maximum absorption in the mobile phase. The linear range of determination for bupropion hydrochloride is between 2.12 and 21.2 μg·mL -1. The proposed method was validated with respect to accuracy, precision, limits of detection and quantification and robustness, etc.

A Method for Detecting Adhesive Related-Factors of Streptococcus suis Serotype 2 by Real-time PCR

[Objective] This study aimed to establish a method for quantitative detection of mRNA transcriptional level of SS2 adhesive related-factors of Streptococcus suis serotype 2 （SS2） by fluorescent quantitative PCR. []Vlethod] The gene fragments en- coding SS2 adhesive related-factors MRP, FBPS and CPS2J and a housekeeping gene aroA were amplified by reverse transcription PCR from the total RNA of SS2, cloned, and sequenced. The recombinant plasmids containing the target genes were constructed, and used as templates in Real-time PCR. [Result] Dynamic curves, stan- dard curves and melting curves of the adhesive related-factors and aroA were ob- tained by the optimized Real-time PCR system. The standard curves showed a good linear relationship between template copy number and circulation number, and the correlation coefficients （FF） of the standard curves were over 0.995. Also, these as- says were highly specific a^d there was single specific melting peak for every gene. Moreover, the assays were highly sensitive and had a detection limit of 1.0×102 copies in 1 μl of initial templates. Finally, it was highly repeatable and had a coeffi- cient of variation less than 2% for intra-assay. [Conclusion] This study will provide a way to reveal the adhesion mechanism of SS2 to different host cells at molecular level.

Development and Validation of a Novel Reverse Phase HPLC for Determination of Aloperine in Aloperine Tablets

Aim To develop a reverse phase HPLC method for the determination of aloperine, an alkaloid that is newly extracted from Sophora alopecuraides and has shown wide pharmacological effects including antibacterial and antiinflammatory actions. Methods The samples were analyzed on a ODS column with methanol water triethylamine (3∶97∶0 1 V/V) as a mobile phase. The flow rate was 1 0 mL·min -1 , and UV detection wavelength 205 nm. Results Linear regression equation was A=1 6920C+1 7455 (r 2=0 9999, n =5) in concentratins ranging from 20 to 120 μg·mL -1 . The recoveries were 101 2±1 46 % at 80 μg·mL -1 , 100 5±0 75% at 100 μg·mL -1 , and 100 7±1 10% at 120 μg·mL -1 , respectively, and the precisions of aloperine within or between run were from 0 80% to 1 98% ( n =5). The relative contents of aloperine in three lots of tablets were 101 59±1 38%, 98 46±0 23%, and 99 41±1 09% ( n =3). Conclusion The newly developed reverse phase HPLC method is simple and useful for daily assay of aloperine tablets and can overcome the interference from excipient and other alkaloids in titration and UV detection.

A NOVEL OVER-VOLTAGE PROTECTION METHOD FOR 600V SPIC

A novel over-voltage protection method for 600V SPIC (Smart Power IC) is proposed in this paper. The combining FFLRs (Floating Field Limiting Rings) system is designed to be a voltage detector. The detector's voltage can turn off the switch of the APFC (Active Power Factor Correction) circuit and the bus voltage would fall from 600VDC to 300VDC, so the SPIC and power devices can be protected. The advantages of this design are that the total protection circuits are integrated in SPIC and technologically compatible with CMOS or BCD(BipolarCMOS-DMOS) technology.

Automated visual position detection and adjustment for optical waveguide chips and optical fiber arrays

The alignment coupling between optical waveguide chips and optical fiber arrays is the basis of the alignment coupling of planar optical waveguide devices, and the precise position detection with angle and spacing adjustments is one of the key steps of alignment coupling. A methodology for position detection, and angle and spacing adjustment was proposed for optical waveguide chips and optical fiber arrays based on machine vision. The experimental results show angle detection precision levels higher than 0.05°, line detection precision levels higher than 0.1 μm, and detection time less than 2 s. Therefore, the system developed herein meets the precise requirements necessary for position detection, and angle and spacing adjustments for optical waveguide chips and optical fiber arrays.

Fast species identification of mycobacterium by rpoB gene chip technology

Based on rpoB gene micro array as target gene, we are going to use gene chip technology to test 24 mycobacterium standard specimens, 8 non-mycobacterium specimens and 86 mycobacterium clinical isolated specimens. As a result, after mycobacterium and non-mycobacterium standard specimens were duplicated by PCR, mycobacterium standard specimens reproduced 360bp DNA fragments; on the other hand, non-mycobacterium specimens did not reproduce any fragments except for hemolytic streptococcus and corynebacterium pseudodiphtheriticum which had the same results as mycobacterium standard specimens. Sensitive test is able to detect lpg tuberculosis mycobacterium DNA. The probe test showed that, among 21 oligonucleotide probes, probe-M. fortuitum and M. marinum were cross-hybrid; the other probes were specific. We used the new method to identify 126 mycobacterium clinical isolated specimens. The test results of this new method matched with conventional method. In conclusion, compared to the traditional method, the use of rpob gene chip technology to identify mycobacterium species will be faster, more accurate and higher value in application.

Use of Chlorophyll Fluorescence Methods for the Study of Physiological Condition and Resistance against Abiotic Factors of Grapevine

The purpose of this study was to explore influence of abiotic factors, such as high temperature, water deficiency and high solar radiation on the photomembrane of grapevine leaves. Grapevine leaves were collected from variety Rkatsiteli （Vitis vinifera） and placed at a temperature of ＋45 ℃ and ＋55 ℃ for 5 rain, respectively. The relative volume of water in leaves was gradually reduced to 50%, and then leaves were irradiated with 6,000 pmol/m2.s of white light. Changes provoked by stressful abiotie factors were determined using rapid and delayed chlorophyll fluorescence methods. It was shown that value of variable component of chlorophyll fluorescence （Fv）, intensity of electron transport between the photosystems （ETR）, intensity of expended electrons in carboxylation （ETRn） and oxygenation （ETRp） and index of non-photochemical quenching （NPQ）, allow studying molecular mechanisms of the impact of abiotic factors and the resulting damage degree. Based on delayed and rapid fluorescence data, it was demonstrated that temperature of ＋45 ℃ adversely affects oxygen production system and CO2 assimilation mechanisms, while at ＋55 ℃, the ETR decreases. Reduction of relative water volume in leaves up to 50%-55% leads to sharp reduction in ETR and inhibition of photosynthesis. In case of irradiation of leaves with high-intensity light of 6,000 μmol/m2.s, NPQ of light falling on a leaf increases, thus protecting photosynthesis apparatus from damage.

Electrochemical biosensors and logic devices based on aptamers

Aptamers are molecular recognition elements with high specificity that are selected from deoxyribonucleic acid/ribonucleic acid (DNA/RNA) library. Compared with the traditional protein recognition elements,aptamers have excellent properties such as cost-effective,stable,easy for synthesis and modification. In recent years,electrochemistry plays an important role in biosensor field because of its high sensitivity,high stability, fast response and easy miniaturization. Through the combination of these two technologies and our rational design,we constructed a series of biosensors and biochips that are simple,fast,cheap and miniaturized. Firstly,we designed an adenosine triphosphate (ATP) electrochemical biosensor based on the strand displacement strategy. We can detect as low as 10 nmol/L of ATP both in pure solution and complicated cell lysates. Secondly,we creatively split the aptamers into two fragments and constructed the sandwich assay platform only based on single aptamer sequence. We successfully transferred this design on biochips with multiple micro electrodes (6×6) and accomplished multiplex detection. In the fields of biochips and biocomputers,we designed several DNA logic gates with electric (electrochemical) signal as output which paves a new way for the development of DNA computer.

Simultaneous determination of seven bioactive constituents in Liuwei Wuling tablet by HPLC coupled with DAD

We employed high performance liquid chromatography （HPLC） method coupled with diode array detector （DAD） for the determination of seven major bioactive compounds （forsythoside A, specnuezhenide, phillyrin, schisandrin, schisantherin A, deoxyschizandrin and schisandrin B） in Liuwei Wuling tablet （LWWLT）. The HPLC baseline separation was carried out on an Inertsil ODS-3 column （250 mm×4.6 mm, 5 μm） at 25 ℃ with a gradient elution system composed of 0.1% phosphoric acid solution and acetonitrile. The detection wavelength was set at 230 nm. Calibration curves for seven compounds showed good linear regressions, with correlation coefficients exceeding 0,999 within the tested concentration range. The limits of detection and quantification of each compound were in the range of 0.03-0.28 μg/mL and 0.11-0.87μg/mL, respectively. The relative standard deviation values of precision, stability and repeatability were less than 2.34%. The average recovery of all seven constituents ranged from 96.71% to 103.9%. The validated quantification method was successfully applied for the analysis of 10 batches of commercial LWWLT from Shandong Shibo Jindu Pharmaceutical Co., Ltd. These results would make foundations for quality control and the further pharmacology study of LWWLT.

Bioassay-based dissolution test of Shuanghuanglian tablet

It has been difficult to perform dissolution test on solid preparations of traditional Chinese medicines （TCMs）. TCMs are different from chemical drugs in that their chemical compositions are complicated. The measurement method based on chemical approach alone is incomplete. In order to solve this problem, in this study a bioassay-based dissolution test was developed. Microcalorimetry was used to obtain growth power-time curves and biothermodynamic parameters of Staphylococcus aureus inhibited by the solution of ShuangHuangLian （SHL） tablet, which was dissolved in phosphate buffer （pH 6.8） for different times. The results of the bioassay-based dissolution test of SHL tablet demonstrated that the bioassay method might be a promising alternative for its quality control.

Effect of triple-phase contact line on contact angle hysteresis

Recent studies have shown that the triple-phase contact line has critical effect on the contact angle hysteresis of surfaces.In this study,patterned surfaces with various surface structures of different area fractions were prepared by electron etching on a silicon wafer.The advancing angle,receding angle and hysteresis angle of these surfaces were measured.Our experimental results showed that while the geometry of microstructure and contact line have a minor effect on the advancing angle,they have a significant effect on the receding angle and thus the hysteresis angle.We have shown that the effect of microstructure and the contact line can be described by a quantitative parameter termed the triple-phase line ratio.The theoretical predictions were in good agreement with our experimental results.

A method of separating blended images in space debris observation

Due to the relative movement between space debris and background stars,the blending of objects and stars is ineluctable through observation.It brings down position accuracy of objects and even makes the tracking break down in worse conditions.In view of the difference of geometry between stars and objects in space debris observation,a technique for separating blended objects based on mathematical morphology is presented.It's sufficiently flexible to be applied in image processing,and the blending images can be separated effectively with a high degree of centroid precision.