荧光定量PCR技术检测布鲁菌BMEⅡ0042基因在酸压力下的表达

[目的]为研究热激蛋白在布鲁菌酸压力条件下发挥的作用,对其编码基因之一的BMEⅡ0042基因在酸压力条件下的表达情况进行检测。[方法]提取正常培养条件下及酸性培养条件下布鲁菌16M株总RNA,先将其反转录为cDNA,再利用荧光定量PCR技术(RT-qPCR)检测布鲁菌热激蛋白编码基因BMEⅡ0042在酸压力下的表达情况。[结果]在酸性条件下,布鲁菌BMEⅡ0042基因相对表达量为16S rDNA的6.20倍,表明该基因表达上调。[结论]布鲁菌热激蛋白编码基因BMEⅡ0042在酸压力条件下上调表达,为进一步研究热激蛋白在布鲁菌酸调控网络中发挥的作用奠定了基础。

封闭压力酸溶-电感耦合等离子体光谱法测定钨矿石中的钨

由于钨在酸性介质中极易发生水解生成水合三氧化钨，通常将钨矿石样品碱熔后采用重量法、光度法等传统方法进行测定，但这些方法操作繁琐，称样量较大（0.1~0.5 g）。本文采用封闭压力酸溶分解样品，钨矿石样品在170℃密闭20 h，然后迅速溶解于10%氢氟酸和5%浓硝酸的混合酸中，使钨形成稳定的易溶解的六价配合物，用耐氢氟酸进样系统的电感耦合等离子体光谱仪测定其中钨的含量，方法精密度为1.5%~6.4%（RSD，n=10），检出限为0.039~0.042 μg/g。方法经钨矿石国家标准物质验证，测定值与标准值一致；与分光光度法对照，测定结果吻合。本方法有效地解决了钨在酸性介质中极易水解的问题，溶样时间相对较短（20 h），无需进行赶酸、复溶等步骤，操作简单，可满足钨含量在0.015%~50%范围的钨矿石的日常分析要求。

压力酸浸制备双价聚硅硫酸铝铁及其除藻性能

目的利用钾长石提钾后的固体渣,开发双价多功能絮凝剂,研究其除藻性能,实现钾长石的综合利用,为除藻等水处理提供新型药剂。方法利用压力酸浸(PAL)工艺提取固体渣中的铝、铁,通过引入Fe(II)源,制备得到含Fe(II)的双价聚硅硫酸铝铁(PSAFS),以铜绿微囊藻(Microcystis aeruginosa)为模式藻,研究PSAFS的混凝除藻效果及其与H2O2的耦合效应。结果当硫酸浓度为2.8 mol/kg,固液比为1:3时,在105℃下反应2 h,PAL可提取近100%的铝和85.6%的铁。含Fe(II)的双价聚硅硫酸铝铁新型絮凝剂对于Microcystis aeruginosa具有优异的去除效果,引入Fe(II)可以拓宽絮凝剂应用的p H范围。同时,在H2O2存在时,产品明显增加了藻细胞的失活。结论以钾长石提钾后的固体渣为原料,采用PAL工艺,可绿色经济地制备含Fe(II)的双价PSAFS,是一种具有应用前景的多功能絮凝剂。

封闭压力酸溶-ICP-MS法分析地质样品中47个元素的评价

对封闭压力酸溶 ICP MS法同时测定地质样品中 47个元素的效果和适用范围进行了实测评价。并对溶样条件进行了优化。实验结果表明 ,HF HNO3高温高压酸溶是一种有效的样品分解方法 ,在所测定的 47个元素中 ,大部分元素如Li,Be ,Ti,V ,Mn ,Co ,Ni,Cu ,Zn ,As,Zr,Nb ,Mo,Cd ,In ,Sn ,Sb ,Hf,Ta ,W ,Tl,Pb ,Bi等在大多数标样中在三种取样量下都可以得到满意的回收率。而Sc ,Cr,Ga ,Y ,REE ,Rb ,Cs ,Sr,Ba ,Th ,U等元素在大部分样品中则随取样量减少 ,回收率上升。在一些样品中 ,当取样量降至 2 5mg时 ,可以获得满意的回收率。用王水代替HNO3复溶残渣 ,利用氯离子的络合作用促进复溶 ,使许多元素的回收率有了明显的提高。

密闭压力酸溶-电感耦合等离子体质谱法测定岩浆岩中稀有元素

利用密闭压力酸溶法对岩浆岩样品进行消解,以酒石酸为络合剂防止Zr、Hf、Nb和Ta的水解,电感耦合等离子体质谱法(ICP-MS)测定Li、Be、Rb、Cs、Nb、Ta、Zr和Hf。研究了密闭压力酸溶条件对稀有元素测定准确度的影响,最优消解条件为:50mg样品,HF和HNO_3用量分别为2.0mL和0.5mL,190℃下消解12h。酒石酸溶液作稀释剂(稀释因子为500),该方法的检出限为0.01～1.69μg/g,相对标准偏差(RSD)为1.43%～7.29%。优化后的密闭压力酸溶法可提高稀有元素的溶出率,具有快速、简便、准确度和精密度高等优点,适用于地球化学样品的批量检测。

封闭压力酸溶-电感耦合等离子体质谱法同时测定电气石中29种元素

电气石是一种含硼的铝硅酸盐矿物,是重要的非金属矿产资源和成岩成矿作用的灵敏示踪剂,因类质同象置换普遍使其组成成分多变,主量元素为Si、B、Al、Fe和Mg,微量元素有稀土元素、Cu、Pb、Zn、Sn、Ag和Sr等。电气石的化学性质非常稳定,不能被一般的酸或碱完全溶解,本文采用硝酸-氢氟酸封闭压力溶矿,50%王水封闭压力复溶进行样品前处理,建立了电感耦合等离子体质谱法测定电气石中稀有轻金属、重金属、放射性金属、稀土元素等29种元素的分析方法。方法检出限为0.003~0.4μg/g,精密度(RSD,n=12)为0.9%~9.2%;国家标准物质的测定值与标准值基本相符,各元素的加标回收率为95%~105%。本方法解决了电气石样品难分解、复溶时易出现氢氧化铝微细残渣的问题,样品试液中B、Al、Fe等主要共存离子的干扰小,各待测元素测定结果准确、可靠。

封闭压力酸溶-电感耦合等离子体发射光谱法测定电气石中16种元素

采用电感耦合等离子体发射光谱法测定电气石中铝、铁、钙、镁、钛、钾、钠、锂、钒、铬、锰、磷、钴、镍、锶、锌等16种元素的含量。考察了不同溶样方法对电气石样品的分解效果,研究了铝、铁等基体元素对被测元素的干扰及消除,最终选择采用HNO 3-HF封闭压力溶矿,50%王水封闭压力复溶,进行样品分解。分析方法检出限为0.1~15μg/g,方法精密度(RSD,n=12)为0.2%~2.9%,样品各元素的加标回收率为95%~104%。方法用于三类电气石样品的测定,主量元素测定结果与化学分析的结果基本一致。

基于RNA-seq识别布鲁菌酸调控候选基因

布鲁菌作为胞内寄生菌,在胞内生存面临很多压力。特别是感染早期,胞内的酸化是布鲁菌生存的必要条件。本试验利用RNA-seq,对正常培养条件、酸性培养条件的布鲁菌进行比较转录组学分析。结果表明,在酸性条件下113个基因表达发生显著变化(IlogRatiol≥3),其中44%表达上调。经pathway分析,差异基因分布在51个通路,其中与布鲁菌胞内生存及毒力相关的通路有6个,分别是氧化磷酸化、离子转运、细菌分泌系统、转录调节系统、二元转运调控系统和ABC转运系统。布鲁菌对于酸性生存环境表现多通路、多基因的适应性变化,该研究为系统掌握酸调节基因奠定基础。

姬塬油田D3区C1油藏暂堵酸化工艺应用评价

姬塬油田D3区C1油藏主要为三角洲前缘水下分流河道沉积,属于特低渗岩性油藏。油藏地层水水型为氯化钙水型,与注入水配伍性较差,油井见水后在近井地带发生堵塞,造成油井油量下降,含水上升。本文主要对C1油藏见水机理进行分析,并分析暂堵酸化解堵技术在实际应用中的效果。

封闭酸溶-等离子体质谱法分析超细粒度地质样品中42个元素

采用封闭压力酸溶,电感耦合等离子体质谱法(ICP-MS)测定了超细样品的42个元素,研究了样品的粒度、分解条件、取样量对分析准确度和精密度的影响。结果表明,用超细粉碎样品(<30μm),取样量减小至2mg仍能保证取样代表性,总用酸量可减至0.5mL,反应时间也可大大缩短。采用超细样品可更好地发挥ICP-MS技术高灵敏度的效能,从而达到保护环境、降低分析成本、提高分析效率的目的。

邯钢酸洗线工艺设备创新及生产控制软件开发

通过对酸洗工艺设备的创新及工艺控制软件的开发,整体提高酸洗带钢实物质量水平,避免了水边、锈蚀等缺陷的产生,酸槽内酸流量稳定、酸液压力稳定,同时现场产品信息和生产关键参数实现自动记录,降级品管理规范明确,提高产品质量等级的同时,实现了高效化生产。

大肠杆菌抗酸碱环境的分子机制

细胞抗酸碱机制是一个重要的分子生物学问题,也是当前国际上非常活跃的研究前沿领域。大肠杆菌的抗酸系统中,与代谢相关的抗酸机制是利用氨基酸脱羧酶消耗氨基酸特定的氢离子,产生胺类和CO2,最终提高pH值。周质空间的抗酸机制,主要是依靠分子伴侣来保护周质空间中蛋白质。细菌二元调控系统可以感知极端pH环境等外界刺激,激活或抑制靶基因的表达,使细胞做出应答。非编码小RNA的抗酸途径则通过增加Rpo S或者降低H-NS的翻译来实现。关于大肠杆菌抗碱机制的研究甚少,至今只发现gad C、rpo S、nha A和tna A四个基因可能帮助大肠杆菌细胞耐受极碱环境。揭示大肠杆菌抗酸碱途径的生物学机制,对人肠道致病菌的治疗和预防都有着积极的作用,也能为生物医药的研究提供可靠的分子依据和新药开发的新靶点。

地面压力监测自动记录仪的应用

地面压力监测自动记录仪能实时、完整、自动地记录监测压力变化的全过程 ,并对一些压力特征点进行自动检测、判断和报警 ,为现场施工提供及时、准确和可靠的压力数据。其智能化程度高 ,在对射孔监测、酸化压力监测。

渤海蓬莱油田注水井酸化摩阻的确定及对酸化效果的影响

由于蓬莱油田注入水水质差,注水井堵塞快,为保证油田注水量需开展大量水井酸化,成本较高,为了降本增效,急需提高酸化技术水平。由于酸化工艺最重要的两个参数是压力和排量,而且酸化摩阻的计算直接影响着酸化压力。结合实例,该文章对酸化摩阻进行了研究,发现传统酸化摩阻按照配注量计算,得到的井口酸化压力是个定值,实际上酸化排量通常比配注量大,导致摩阻计算偏小,酸化压力也会偏小。为此,该文提出了酸化摩阻和井口酸化压力应随酸化排量改变的观点,在实际应用中,水井酸化效果得到明显改善。

高温深层碳酸盐岩储层酸化压裂改造技术探析

近几年,油气勘探技术得到了快速发展,勘探范围逐渐扩大,人们加强了对勘探的研究,其中碳酸盐岩层是油气勘探过程中经常会遇到的地质结构,因此得到了人们的重视。碳酸盐油气具有温度高、埋藏深、非均匀质性强等诸多特点,在具体研究与分析过程中要对应用的技术及理论研究、现场应用等诸多内容进行重点分析,从而为碳酸盐岩储层开发提供强有力的技术支持。

Analysis on the Relationship between Selective Pressure and Nucleotide Substitution Rate in Nucleus and Organelle Genes of Sorghum and Maize

[Objective]The aim was to research the relationship between nucleotide substitutions rate and selective pressure.[Method]Synonymous and nonsynonymous substitutions and their ratios for some sorghum and maize genes in nucleus and organelle genomes were analyzed by statistical method,and comparative analysis of related functional genes were carried out.[Result]The pure selective pressures of the related functional genes were similar between nucleus and chloroplast genomes,but was lower in mitochondrial genome.The significant differences of nucleotide substitution rate between sorghum and maize orthologous genes in nucleus genome,and among different functional genes in nucleus genome were mainly due to the nonsynonymous substitution difference.[Conclusion]The molecular evolutional rate of different functional genes and different lineages were influenced by selective pressure.The differences of molecular evolutional rate among nucleus,chloroplast and mitochondria genomes had no direct relationship with selective pressure.

Sphincter of Oddi hypomotility and its relationship with duodenal-biliary reflux,plasma motilin and serum gastrin

AIM: To detect whether patients with a T tube after cholecystectomy and choledochotomy have duodenal-biliary reflux by measuring the radioactivity of Tc99m-labeled diethylene triamine penta-acetic acid (DTPA) in the bile and whether the patients with duodenal-biliary reflux have sphincter of Oddi hypomotility, by mea-suring the level of plasma and serum gastrin of the patients. Finally to if there is close relationship among sphincter of Oddi hypomotility, duodenal-biliary reflux and gastrointestinal peptides. METHODS: Forty-five patients with a T tube after cholecystectomy and choledochotomy were divided into reflux group and control group. The level of plasma and serum gastrin of the patients and of 12 healthy volunteers were measured by radioimmunoas-say. Thirty-four were selected randomly to undergo choledochoscope manometry. Sphincter of Oddi basal pressure (SOBP), amplitude (SOCA), frequency of con-tractions (SOF), duration of contractions (SOD), duo-denal pressure (DP) and common bile duct pressure (CBDP) were scored and analyzed. RESULTS: Sixteen (35.6%) patients were detected to have duodenal-biliary reflux. SOBP, SOCA and CBDP in the reflux group were much lower than the controlgroup (t = 5.254, 3.438 and 3.527, P < 0.001). SOD of the reflux group was shorter than the control group (t = 2.049, P < 0.05). The level of serum gastrin and plasma motilin of the reflux group was much lower than the control group (t = -2.230 and -2.235, P < 0.05). There was positive correlation between the level of plasma motilin and SOBP and between the level of serum gastrin and SOBP and CBDP. CONCLUSION: About 35.9% of the patients with a T tube after cholecystectomy and choledochotomy have duodenal-biliary reflux. Most of them have sphincter of Oddi hypomotility and the decreased level of plasma motilin and serum gastrin. The disorder of gastroin-testinal hormone secretion may result in sphincter of Oddi dysfunction. There is a close relationship between sphincter of Oddi hypomotility and duodenal-biliary re-flux.

Viscosities of Pure Water, Acetic Acid ＋ Water, and p-Xylene ＋ Acetic Acid ＋ Water at Different Temperature and Pressure

The viscosities of pure water,the acetic acid+water binary system,and the p-xylene+acetic acid+ water ternary system at different concentrations were determined with a rolling-ball viscometer at temperatures from 313.15 to 473.15 K and pressures from 0.10 to 3.20 MPa.The viscosity data were fitted by a correlation equation for the estimation of the mixture viscosities.The average absolute deviations(AAD)of the correlation for binary and ternary systems are 2.48%and 1.77%,respectively.

Injection molding of micro patterned PMMA plate

A plastic plate with surface micro features was injection molded to investigate the effect of pressure rise of melt on the replication of the micro structures. Prism pattern, which is used in many optical applications, was selected as a model pattern. The prism pattern is 50 μm in pitch and 108° in the vertical angle. The overall size of the plate was 335 minx213 mm and the thickness of the plate varied linearly from 2.6 mm to 0.7 ram. The prism pattern was firstly machined on the nickel plated core block using micro diamond tool and this machined pattern core was installed in a mold for injection molding of prism patterned plate. Polymethyl methacrylate （PMMA） was used as a molding material. The pressure and temperature of the melt in the cavity were measured at different positions in the cavity and the replication of the pattern was also measured at the same positions. The results show that the pressure or temperature profile through the process depends on the shape and the size of the plate. The replication is affected by the temperature and pressure profiles at the early stage of filling, which is right after the melt reaches the position to be measured.

Novel Control Structure Design of Differential Pressure Thermally Coupled Reactive Distillation for Methyl Acetate Hydrolysis

In this paper, the novel control structures of differential pressure thermally coupled reactive distillation process for methyl acetate hydrolysis were proposed. The RadFrac module of Aspen Plus was adopted in the steady-state simulation. Sensitive analysis was applied to find the stable intial value and provide a basis for the improved control structure design. The Aspen Dynamics software was adopted to study the process dynamic behaviors, and two novel control structures provided with feed ratio controllers and sensitive tray temperature controllers were proposed. The reflux ratio controllers were applied in the improved novel control structures. Both control structures abandoned the composition controllers that were replaced by simpler controllers with which the product purity could meet the specification requiring under a ± 20% disturbance to the total feed flowrate / MeAc composition.