空气喷射变形丝的芯吸效应

利用毛细管上升法和液滴吸收法研究了聚酯、黏胶、聚酰胺、聚酯/黏胶和聚酯/聚酰胺空气喷射变形丝的芯吸率和吸湿率。结果表明,空气变形后复丝的芯吸率提高。与聚酰胺和黏胶空气喷射变形丝相比,聚酯空气喷射变形丝显示出较大的芯吸率。黏胶空气喷射变形丝显示出最低的芯吸率。与同样的未变形丝相比,混合的空气喷射变形丝显示出较大的芯吸率。     

双罗纹针织物的吸湿性研究

开发具有吸湿性的特殊用途织物,如需剧烈运动时穿着的运动休闲装和运动服,多层织物在这些应用上展示出许多的特点.所选织物具有良好的热湿舒适性,如具备润湿、芯吸、透湿、透气和导热的特性.     

嗜酸乳杆菌冻干影响因子的研究

传统的乳酸菌发酵剂因活化过程复杂,极易引起污染而影响发酵乳的质量。目前,多采用冷冻干燥技术制备直投式粉末状乳酸发酵剂。然而,菌种冻干时机的把握和冻干保护剂的选择,将直接影响乳酸菌在冷冻干燥前后的存活率以及存活期。本文研究了嗜酸乳杆菌的生长曲线,选用蔗糖、乳糖、甘油、VC、谷氨酸钠、麦芽糊精、脱脂乳粉等为嗜酸乳杆菌冻干保护剂进行了冻干研究。结果表明:①嗜酸乳杆菌发酵液培养至酸度为100°T、pH值4.8时,OD410nm=0.511为最大,是最佳发酵终止时间;②嗜酸乳杆菌冻干保护剂配方以5%麦芽糊精、2%VC、5%甘油为最佳冻干保护剂组合,此时嗜酸乳杆菌冻干菌粉活菌数为2.34×109cfu/g。     

Study on Superabsorbent Composite, 14

Summary: Organo‐attapulgite (organo‐APT) was prepared by modifying APT using four quaternary ammonium salts with various lengths of the alkyl group, including (octyl)trimethylammonium bromide (OTMABr) and (stearyl)trimethylammonium chloride (STMACl), etc. A series of composite hydrogels, poly(acrylic acid)/organo‐APT, from acrylic acid (AA), and organo‐APT was prepared by aqueous polymerization, using N,N′‐methylenebisacrylamide (MBA) as a crosslinker and ammonium persulfate (APS) as an initiator. The organification and organification degree of APT as well as the corresponding composites were characterized by FTIR, TGA, and XRD. The effects of the length of the alkyl group for different quaternary ammonium salts, organification degree of APT, and organo‐APT content on water absorbency and swelling behaviors in various electrolyte solutions were investigated in this study. Equilibrium water absorbency strongly depends on chain length of the alkyl group of quaternary ammonium salts, organification degree of APT as well as organo‐APT content. Longer alkyl group, higher organification degree, and proper organo‐APT content are of benefit for the improvement of equilibrium water absorbency. Equilibrium water absorbency in distilled water for PAA/APT was enhanced from 350.1 to 562.1 g · g^?1 after 10 wt.‐% organo‐APT, modified with STMACl for the highest degree, was introduced. The kind of cation is the key factor influencing equilibrium water absorbency of these composite hydrogels in electrolyte solutions. Organification of APT could enhance responsiveness of the corresponding composite hydrogel to electrolyte solutions.

Schematic structure of PAA/organo‐APT composite in a dry state (left) and in a swollen state (right).     

Preparation of new sunscreen materials Ce1-xZnxO2-x via solid-state reaction at room temperature and study on their properties

Superfine cerium-zinc oxides Ce1-xZnxO2-x with x = 0, 0.1, 0.3, 0.5, and 1.0 were obtained by grinding Ce(SO4)2·4H2O, ZnSO4·7H2O and NH4HCO3 under the condition of surfactant PEG-400 being present at room temperature, washing the mixture with water to remove soluble inorganic salts, drying at 80°C, and calcining.The precursor and its calcined samples were characterized using thermogravimetry and differential thermal analyses(TG/DTA), UV-vis absorption spectroscopy, X-ray powder diffraction(XRD), and scanning electron microscopy(SEM).The results showed that superfine Ce1-xZnxO2-x behaved as an excellent UV-shielding material.The ZnO-doped CeO2 can facilitate the formation of crystalline state CeO2.The catalytic ability of products used in air oxidation of castor oil was investigated.The results showed that the catalytic abilities of products decreased with increasing zinc amount.     

不同离子类型对土壤保水剂吸释水特性影响研究

保水剂因其吸水极强,且对所吸收的水分具有高度的保持作用及反复吸水功能,成为保持土壤水分的有效途径之一。选择常用的"科翰98"、北京汉力淼、法国爱森3种类型保水剂,对保水剂在去离子水中的反复吸释水特性以及不同离子类型对保水剂反复吸释水能力的影响进行研究。结果表明:不同类型、粒径保水剂随着反复吸释水次数的增加,吸水倍率降低。保水剂反复吸释水能力顺序为:爱森>汉力淼>科瀚;大粒径比小粒径降幅更大。各保水剂反复吸释水特性与粒径不成线性规律变化。在反复吸释水条件下,各保水剂吸水速率均高于第1次吸水速率。随着吸释水次数的增加,保水剂凝胶达到饱和的时间提前,对于科瀚影响效应最为明显。2+离子对保水剂的反复吸水能力影响更为显著,其次为1+离子。Zn2+最易使保水剂失效,KNO3对保水剂的影响在前期略大。     

溶液中钼的快速测定

采用光谱纯MoO3来配置标准钼溶液，然后利用硫氰酸盐分光光度比色法测得钼浓度与吸光度的关系曲线：c=0．3972×A。利用该关系式对钼冶金生产中浸出液的钼含量进行了分析测定，并通过对浸出渣中钼含量的分析测定来校核，结果显示两者具有良好的一致性，其相对标准误差为0．34％。此外，用同样方法和操作步骤对某冶炼厂废水中的钼含量进行了测定和校核，两者的结果也能较好吻合，其相对误差为0．29％。     

黄原胶接枝丙烯酸高吸水性树脂的制备及性能研究

采用黄原胶为原料与丙烯酸接枝共聚制备了高吸水性树脂,考查了合成条件对所制得的高吸水性树脂吸水性能的影响.结果表明,在聚合温度为65℃,丙烯酸单体∶黄原胶=5∶1(质量比),丙烯酸中和度为75%,引发剂和交联剂与丙烯酸单体的质量比分别为0.08和0.031时,所得树脂的吸水倍率可达1026 g.g-1,吸盐水倍率达到716 g.g-1,且吸水速率适中,保水性能较好,是一种新型的环保型高吸水性树脂.     

铌铁中Al、P的快速测定方法研究

试样以过氧化钠熔融后用水浸取,定溶后干过滤,使铝于铁、铌等干扰元素分离,加过量EDTA再调PH值于4.5左右,使铝完全络合,以PAN为指示剂,用硫酸铜标准溶液回滴过量的EDTA,加入氟化钠使Al-EDTA解蔽,释放出与铝等量的EDTA,再用硫酸铜标准溶液滴定,由此计算Al的含量。分取滤液以钼酸铵-酒石酸钾钠混合溶液掩蔽硅并使磷生成“磷钼黄”,以氟化钠-二氯化锡掩蔽铁并将“磷钼黄”还原成“磷钼蓝”,测量吸光度。     

土壤成分的测量与控制

土壤配方施肥的前提是准确测量土壤肥力、植株养分、土壤PH值及土壤的含水量。作者就土壤成分测量的研究项目从单片机控制的角度叙述了分析仪的整体功能，然后从电路原理 的角度重点阐述了养分及PH值的高精度测量方法。