25℃Na~+,K~+∥Cl~-,SO_4~(2-)-H_3BO_3-H_2O体系相平衡研究

实验测定了２５℃Ｎａ＋,Ｋ＋∥Ｃｌ－,ＳＯ２－４－Ｈ３ＢＯ３－Ｈ２Ｏ五元体系的溶解度并对所绘相图进行了分析,讨论了硼酸的分离及其对硫酸钠转化制硫酸钾的影响     

25℃Na^＋,K^＋∥Cl^—,SO^2—4—H3BO3—H2O体系相平衡研究

实验测定了２５℃Ｎａ＾＋,Ｋ＾＋∥Ｃｌ％－２,ＳＯ＾２－４－Ｈ３ＢＯ３－Ｈ２Ｏ五元体系的溶解度关对所绘相图进行了分析,讨论了硼酸的分离及其对硫酸钠转化制硫酸钾的影响。     

从芒硝矿中制取硫酸钠的方法

本发明属于从芒硝矿中制取硫酸钠的方法,在加工卡拉博加兹哥尔湾得到的芒硝矿时可以应用此法。通过盐湖天然卤水盐析作用的办法从芒硝矿中制取硫酸钠的方法乃是已经知道的。所得到的成品质量不高以及能耗大则是上     

一步法提取硫酸钠的工业应用

利用硫酸钠在不同酸浴温度下，结晶析出硫酸钠晶体形式不同的原理，采用“一步法提取硫酸钠”工艺，在高温的情况下直接从酸浴中提取出无水硫酸钠晶体，省去了目前处理酸溶中采取的低温结晶析出芒硝、焙烧工艺生产元明粉的“两步法提取硫酸钠”工艺，具有显著的节能、环保、减少设备投资、减少人力、降低生产成本等优点。     

硫酸钠型矿卤制取硫酸钙品须的工艺研究

江苏省淮安地区的岩盐资源经钻井水溶法得到硫酸钠型次饱和卤水,在对其进行日晒制盐的过程中,产生大量的盐石膏（CaSO4·2H2O）和无水芒硝（Na2SO4）,其综合利用价值不高。本文对利用硫酸钠型矿卤制取硫酸钙晶须的工艺进行了研究,提出了先对硫酸钠型次饱和卤水进行除硫处理,处理后的母液用于日晒制盐,将得到的CaSO4·2H2O通过溶解、加热、过滤、冷却结晶转化生产硫酸钙晶须,为硫酸钠型卤水资源的综合利用提供了一条新的技术路线。     

盐硝联产盐母液硝含量控制之我见

本文从影响盐硝联产系统稳定、可靠的几方面因素分析，提出了盐系统Ⅳ效母液硫酸钠的控制含量。     

氯化钠-硫酸钠-水三元体系相平衡

采用等温法，在15℃和20℃下测定了氯化钠和硫酸钠在水中的相互溶解度数据，得到了平衡液相组成的密度和折光率。     

月桂醇聚氧乙烯醚硫酸钠的提纯

采用乙酸乙酯重结晶法提纯市售的月桂醇聚氧乙烯醚硫酸钠(70%)。提纯后,得到了表面张力满足表面化学实验研究所用的月桂醇聚氧乙烯醚硫酸钠。     

蛋白质检验中的关键点

0　前　言蛋白质含量的高低直接影响食品质量的好坏。因此 ,食品中蛋白质含量是必检指标。在检验中 ,作者发现有几个问题 ,直接影响检验工作的顺利进行 ,从而影响检验数据的准确性。1　蛋白质的检验原理首先在硫酸铜、硫酸钠 (钾 )的催化下 ,利用浓硫酸将试样消化 ,令其中的含氮物质转化成铵盐溶液 ;然后在强碱、加热条件下 ,将铵盐转化成氨气放出 ,并利用硼酸溶液将放出的氨气吸收 ;之后 ,用盐酸标准溶液对吸收了氨气的硼酸溶液进行滴定。最后 ,可通过公式计算出试样中的蛋白质含量。2　蛋白质检验中的注意点2 .1　选用合适的蒸馏方法 ,减…     

利用硫酸钠型卤水生产食盐过程对于硫酸钠的分离

多年来,以矿盐人工卤水生产食盐中,完全地分离硫酸钠,迄今尚未得到很好解决,故生产的食盐达不到国家规定的质量标准,造成产品质量低劣,而硫酸钠又是造纸、合成洗涤剂、维尼龙、染料、玻璃等工业不可缺少的原料,是国家急需的产品。现在各盐矿分离提制硫酸钠,过程复杂、维修     

固体酸催化合成肉桂酸甲酯

固体酸能够代替硫酸作为酯化催化剂。介绍了对甲苯磺酸、氨基磺酸、强酸性阳离子交换树脂、六水三氯化铁、聚氯乙烯三氯化铁树脂、五水四氯化锡、十二水合硫酸铁铵、一水硫酸氢钠、硫酸氢钾、硼酸、固体超强酸和杂多酸等固体酸催化合成肉桂酸甲酯的方法。     

硼钨杂多酸盐催化合成柠檬烯-1,2-环氧化物的工艺优化

为提高柠檬烯-1,2-环氧化物收率,采用正交试验法,优选硼钨杂多酸盐的最佳制备工艺。通过单因素试验研究了催化剂制备工艺中稀硫酸-钨酸钠物质的量比、钨酸钠-硼酸物质的量比、十六烷基三甲基氯化铵（cetyltrimethyl ammonium chloride,CTMA）-钨酸钠物质的量比、合成温度及合成时间对柠檬烯-1,2-环氧化物收率的影响,利用正交试验法优化最佳制备工艺条件。结果：当稀硫酸-钨酸钠物质的量比1.5∶1、钨酸钠-硼酸物质的量比3∶1、CTMA-钨酸钠物质的量比1∶3、合成温度80 ℃、合成时间1 h时,柠檬烯-1,2-环氧化物的收率可达到4.351 6%。对最优条件下制备的催化剂进行表征分析,表明硼酸、季铵盐均已成功接枝到活性中心上,并且硼钨杂多酸盐催化剂保持Keggin结构的基本骨架,是一种微孔的晶体结构,分子式为C19H44W3BNO18。     

凯氏定氮法检测脱脂奶粉中蛋白质的含量

脱脂奶粉与浓硫酸、硫酸铜、硫酸钾一同加热硝化，反应生成（NH4）2SO4，其在碱性条件下蒸馏，释放出NH3，用硼酸吸收后，再以盐酸标准溶液滴定，计算出蛋白质含量．     

Comparative Study of Different Milk Samples Preservation Procedures for Bacteriologic Examination

The control of pathogenic bacteria present in foods, as well as scientific data concerning their behavior, are closely linked to analytical methods used and the way they are implemented. To assess the capacity of the laboratories to conduct correctly microbiological analyses, national and international proficiency testing schemes are organized. To set up these inter-laboratory studies (ILS), it is necessary to prepare artificially contaminated samples, which contamination level is sufficiently stable regarding their transportation conditions to the participating laboratories. In this context, we tested several procedures to maintain the concentration of Listeria monocytogenes and coagulase-positive staphylococci in milk samples: freezing temperature and addition of bacteriostatic agents at refrigeration temperatures, such as nystatin, boric acid, sodium azide, the lactoperoxidase system, or a boric acid mixture. Through this study we selected preservation procedures, which could be used to stabilize the contamination level of artificially contaminated milk samples during transportation without preventing the growth of the target bacteria during the analysis and after the initial dilution step. Boric acid mixture and boric acid were found to be effective in stabilizing the contamination level of Staphylococcus aureus in milk samples, whereas freezing, a boric acid mixture, and boric acid were suitable for milk samples containing L. monocytogenes, depending on the samples’ contamination rate. An erratum to this article can be found at     

聚羧酸盐在棉织物X型活性轧染中的应用研究

纯棉织物X型活性染料轧染时，使用聚丙烯酸盐（PA）和聚马来酸盐（PM）代替Na2SO4作促染剂。通过比较染色织物的表观色深（K／S值）、各项牢度和强力指标，探讨了聚羧酸盐作为促染剂应用于纯棉织物X型活性染料轧染工艺的可行性，并得出了最佳染色工艺条件。试验结果表明，当聚羧酸盐用量为50g／L时，染色织物的K／S值、各项牢度指标和强力均与用Na2SO4作促染剂时相当。     

高分散性白炭黑生产新工艺探究

以液体水玻璃和稀硫酸为主要原料,在反应过程中通过添加可溶性铝盐如:硫酸铝、铝酸钠等来提高产品的分散性,改变了添加反应母液的传统方式。将配制好的水玻璃溶液、稀硫酸、铝酸钠溶液以一定的温度、浓度、流速、流量在反应器中反应,然后酸化、洗涤、干燥得到高分散白炭黑成品。     

荧光光度法对水解胶原蛋白与铬络合物作用的模拟研究

通过荧光光度法,用硫酸铬、甲酸钠及甲酸与水解胶原作用,为认识铬鞣及铬鞣机理提供更多的证据。结果表明:水解胶原蛋白中加入硫酸铬溶液,其荧光强度在315 nm处有不同程度的降低;加入硫酸铬溶液的同时,引入相同量的甲酸钠,此时荧光猝灭更明显;在一定条件下,水解胶原的pH对水解胶原荧光猝灭最明显,这可能是pH的变化引起水解胶原疏水性变化的结果。     

Boron fixation in wood: studies of fixation mechanisms using model compounds and maritime pine

The purpose of the research work reported in this paper was to study the kinetics and thermodynamics of reactions of some boron compounds with some simple wood model compounds and with maritime pine (Pinus pinaster Ait.). The wood model compounds were selected in order to reproduce in a simple way the possible reactions boron may undergo with wood. Two boron compounds were tested with the wood: sodium tetraborate decahydrate (borax) and boric acid. Boron containing solutions applied to wood and model compounds were tested in such a way that they could lead to the insolubilization of boron or to its chemical fixation. Thermodynamics of boric acid fixation on the wood surface was studied. Results suggest that, even though boron reacts faster with polysaccharides than with lignin, all reactions are very slow at 20 °C. Adsorption should be the preferential mechanism for the bonding of boric acid to wood. This weak bond explains why boron tends to leach out from wood in wet conditions after conventional preservative treatments.     

影响猪胰蛋白酶提取部分工艺因素研究

目的:研究猪胰蛋白酶的提取工艺,提高猪胰脏的利用价值,变废为宝,减少对环境的污染。方法:实验采用Tris-HCl缓冲液为提取剂,硫酸铵盐析和对猪胰蛋白酶的提取及纯化工艺进行了研究。通过单因素实验和正交实验,对影响猪胰蛋白酶收率和活力的诸因素进行了研究,最后确定了最佳工艺条件。结果:所得的最佳工艺条件:料液比1∶5、Tris-HCl浓度0.05mol/L、激活pH8、激活时间6h。结论:所制得的胰蛋白酶比活力为6600BAEE/mg,胰蛋白酶收率为6.5%,该工艺简单,提取效率高,产品酶活高。     

Carbohydrate components of mongolian apricot fruit (Armeniaca sibirica l.). fractional extraction and general characteristics

A procedure for the fractionation of ripe Mongolian apricot fruit (Armeniaca sibirica L.) is described. A water-soluble fraction (31.7% of the dry apricot), obtained from the defatted fruit, contained most of the free sugars, with sorbitol and glucose as the principal components. The cell wall material (9.5% of the fresh fruit) was delignified and successively extracted with EDTA, 5% sodium hydroxide and 17.5% sodium hydroxide+3% boric acid. Subsequent ethanol precipitation, acidification and dialysis yielded a pectic-rich fraction and four hemicellulose fractions. An almost pure water-insoluble L-arabino-(4-O-methyl-D-glucurono)-D-xylan with the molar ratio of xylose, arabinose and uronic acid 10:1.1:0.8 was obtained; it represents the main hemicellulose component of the cell wall material (3.9% of the dry apricot). The remaining α-cellulose (10.1% of the dry apricot) retains about 16% of xylan, originally present in the holocellulose.