聚羧酸盐分散剂在农药水悬浮剂中的应用及作用机理分析

聚羧酸盐分散剂具有独特的分散性能,可显著提高农药水悬浮剂等剂型的稳定性.本文应用3种聚羧酸盐分散剂分别制备了3种农药水悬浮剂,研究了聚羧酸盐分散剂在原药颗粒表面的吸附特征和吸附热力学,研究了聚羧酸盐分散剂对农药水悬浮体系Zeta电势和流变性质的影响,并分析了体系在热贮前后各稳定性参数的变化,最终得到了具有长期储存稳定性的农药水悬浮剂产品.研究结果显示,聚羧酸盐分散剂在原药颗粒表面的吸附符合Langmuir单分子层吸附模型,其中吸附热力学参数?G_(ad)0、?S_(ad)0、?H_(ad)0且|?H_(ad)|40 kJ mol~(-1),表明该吸附为自发进行的、放热、熵增的物理吸附过程.聚羧酸盐分散剂通过提高悬浮体系的Zeta电势,使得分散粒子间相互排斥,改善了体系的流动性能,从而提高农药水悬浮剂产品的长期储存稳定性.     

不同寡聚度磺酸盐表面活性剂与支化羧酸盐混合体系的聚集行为

采用表面张力、Zeta电位和小角中子散射技术,研究了pH 11条件下2-己基癸酸、异硬脂酸对具有单头单链十二烷基磺酸钠（SDoS）和星状四聚磺酸盐表面活性剂EDA-（C₁₂SO₃Na）₄的气液界面性质、胶束化行为和乳化性能的影响.结果表明,在气液界面和胶束中支化羧酸盐分子与磺酸盐表面活性剂间有不同程度的相互吸引作用,而且在降低表面张力效率方面具有协同作用,但胶束中分子间相互吸引作用更强的四聚磺酸盐表面活性剂混合体系在聚集体形成方面却未表现出协同作用.同时,随着羧酸盐的加入,SDoS和EDA-（C₁₂SO₃Na）₄呈现出不同的聚集体转变规律,羧酸盐与SDoS的混合聚集体随着浓度增大逐渐由球形胶束转变为棒状胶束,而羧酸盐与EDA-（C₁₂SO₃Na）₄的棒状胶束随着羧酸盐摩尔分数的增大而增长,随着总浓度的增大而减小.此外,在同等乳化烷烃的效果下,支化羧酸盐分子的加入可以大幅减少寡聚磺酸盐表面活性剂的使用量.     

壳聚糖不饱和羧酸盐聚集行为的研究

以半干法制备了一系列壳聚糖不饱和羧酸盐--壳聚糖水杨酸盐(a1)、壳聚糖苯甲酸盐(a2)、壳聚糖肉桂酸盐(a3)壳聚糖丙烯酸盐(a4)和壳聚糖衣康酸盐(a5).用红外光谱和紫外光谱表征了该产品的结构,以凯氏定氮法测定了羧酸的结合量.结果表明壳聚糖和不饱和羧酸盐是通过壳聚糖上的氨基和羧酸中的羧基发生了成盐反应,羧酸的结合...     

低能氮离子诱发氨基酸前生物合成反应的初步研究

利用氮气火花放电产生离子 ,其中的正离子在阴极位降的加速下“注入”到三种羧酸盐的水溶液中 ,诱发其中的化学反应并沉积在水溶液中 .利用高效液相色谱 (HPLC)对离子注入后的样品进行分析 ,结果表明 ,氮离子注入可使氮沉积在溶液中 ,生成氨及氨基酸 ,这一结果不仅验证了低能离子注入样品时的“质量沉积”效应 ,而且还是原始地球条件下氨基酸生成的一种可能的途径     

电沉积法制备Sn-Co-C锂离子电池负极材料

本文分别采用柠檬酸和EDTA作为络合剂在CoCl2，SnCl4溶液中用电沉积方法制备Sn-Co合金电极，然后在相同条件下在镀液中加入硬碳制备Sn-Co-C复合电极。充放电测试结果显示EDTA作为络合剂时镀层循环性能明显好于柠檬酸，且比容量也较高。Sn-Co合金电极循环30次比容量保持率达91．6％，加入硬碳的Sn-Co-C复合电极比容量及循环性能较之Sn-Co合金电极都有了较大提高。电子探针结果表明EDTA作为络合剂的Sn-Co-C镀层中Sn、Co、C原子比例分别为61．8401％，22．3788％，12．5409％。SEM观察Sn-Co-C镀层表面为稳定的球状结构。     

循环电位沉积Yb-Bi薄膜

利用循环电位沉积法从非水体系中制备了Yb-Bi薄膜。在这一沉积过程中，基体电位是在两个电位之间连续循环的。研究了沉积电位、沉积时间和扫描速率对沉积膜中Yb含量以及表面形态的影响。实验结果表明，在0．10mol．L^-1Ybcl3 0．10mol．L^-1Bi(N03)3 0．10mol．L^-1LiCl DMSO体系中，当控制恰当的沉积条件，可得到表面黑色、均匀、有金属光泽和附着力强的非晶态Yb-Bi薄膜，其中Yb的质量分数可达21．04％～36．36％(质量分数)，所得到的沉积膜通过SEM，EDS和XRD进行了表征。     

化学沉积NiZnP合金及其性能

用柠檬酸钠为络合剂、硼酸为缓冲剂在碱性体系中用化学沉积法由ZnSO4、NiSO4、NaH2PO2和H2BO3制得了NiZnP合金。考察了pH和ZnSO4与(ZnSO4 NiSO4)摩尔比对沉积速度、镀层组成、结构、表面形貌和耐腐蚀性能的影响。发现锌在沉积过程中起阻碍作用,致使镀层中锌含量不高(不超过原子分数20％)。用X射线衍射、透射电镜和扫描电镜等技术研究了镀层的结构和表面微观形貌。结果表明,镀态合金由非晶和少量立方镍两相组成;工艺条件对镀层表面微观形貌有明显的影响。采用浸泡实验和电化学阳极极化实验,重点研究了不同工艺条件的镀层在质量分数为3．5％的NaCl溶液(pH=7．0)中的耐腐蚀性能。结果表明,不同工艺条件所得的镀层耐腐蚀能力不同,NiZnP合金的耐腐蚀性主要与镀层组成有关,含锌量越高、含磷量越低的镀层耐腐蚀性越好。浸泡实验和电化学阳极极化实验的结果是比较吻合的。     

草酸钙的结晶动力学及不同种类羧酸盐的影响

通过检测体系中游离Ca2+离子浓度及草酸钙(CaOxa)的粒径随时间的变化,研究了CaOxa的结晶动力学及3种羧酸盐对CaOxa结晶动力学的影响,这些羧酸盐为:一元羧酸盐甘氨酸钠(NaGlu)、二元羧酸盐酒石酸钠(Na2Tart)和三元羧酸盐柠檬酸三钠(Na3Cit)。在生理盐水中CaOxa的结晶动力学方程为r=kc3.3±0.3,平均反应速率常数(k)为(3.1±1.8)×109;3种抑制剂对k的影响程度从大到小为:Na3Cit>Na2Tart>NaGlu,但其平均反应级数(α)相差不大,α=3.2±0.1。Na3Cit、Na2Tart可抑制CaOxa晶体的生长和聚集过程,是潜在的肾结石抑制剂。     

六氰合铁酸铜钴在蜡浸石墨电极表面的电化学沉积

首次报道了电化学沉积的混合金属六氰合铁酸盐修饰电极作为电流型传感器的研究。针对六氰合铁酸盐修饰电极在中性和碱性条件下的不稳定性，采用混合金属电沉积的方法，成功地提高了电极的稳定性，所得到的修饰电极在 ｐＨ ４～１０之间均表现出良好的稳定性。该电极的响应时间（ｔ９５％）为 ０．５ｓ，并对Ｆｅ３＋／Ｆｅ２＋电对表现出良好的电催化作用。催化氧化峰电流与Ｆｅ２＋的浓度在１．０×１０－４～６．５×１０－２ｍｏｌ/Ｌ范围内呈很好的线性关系，检测下限为 １．４×１０－６ｍｏｌ／Ｌ。     

三苯胺-芴类共聚物的合成及发光性能

在主链上嵌入三苯胺基团来改善聚芴的空穴传输能力、平衡载流子的注入是目前改善聚芴材料发光效率的一种好方法。本文用Suzuki缩聚法合成了芴-三苯胺类共聚物。实验结果表明．在聚芴主链上引入少量的TPA(10％～20％)时．不仅提高了EL效率．而且可以改善光谱的色纯度。TPA含量为20％时,共聚物的EL效率为1．28％。     

Sodium-aluminium-silicates in the washing process part IX: Mode of action of zeolite A additive systems

The mode of action of additives in laundry detergents containing zeolite A has been investigated. Proper additives improve soil removal and reduce deposits on fabrics. They show threshold and carrier effects, which retard aggregation and crystal growth of precipitates and/or accelerate their dissolution in the presence of zeolite A. The results are significant with respect to the formulation of non-phosphate zeolite built laundry detergents.Lecture given at the 7th International Zeolite Conference, New Developments in Zeolite Science and Technology, Tokyo, August 17–22, 1986.     

Swelling and drug release properties of acrylamide/carboxymethyl cellulose networks formed by gamma irradiation

Hydrogels based on acrylamide monomer (AM) and different ratios (5–20 wt%) of carboxymethyl cellulose (CMC) were synthesized by gamma irradiation. The hydrogels were characterized in terms of gel content, swelling and drug release characters. The effect of temperature and pH on the degree of swelling was also studied. The results showed that the gel fraction of AM/CMC hydrogels decreases greatly with increasing the contents of CMC in the initial feeding solution. The kinetic study showed that the swelling of all the hydrogels tends to reach the equilibrium state after 5 h. However, the swelling of AM/CMC hydrogels was greater than the hydrogel based on pure AM. On the other hand, it was found that the swelling of all the hydrogels changes within the temperature range 30–40 °C and within the pH range 4–8. The AM/CMC hydrogels was evaluated for the possible use in drug delivery systems. In this respect, the release properties of methylene blue indicator, as a drug model, was investigated. It was found that the percentage release from the hydrogels increase with time to reach ～80% after 3 h at pH of 2 compared to ～100% at pH of 8.     

漂白粉中总钙量测定方法的改进

采用过氧化氢去除漂白粉中的有效氯,直接测定漂白粉中总钙量,探讨过氧化氢用量,反应时间,试剂加入顺序对实验结果的影响。结果表明,当过氧化氢用量为1.5～4.5 mL,反应时间为3 min时,试剂加入顺序为：过氧化氢―氨性缓冲溶液―Mg2＋-EDTA―铬黑T,体系对测定结果影响最小。用该方法测定了漂白粉中总钙量,其相对标准...     

Rheological and Morphological Properties of Carboxymethylcellulose/Starch Blends with or without ZnO and Their Applications as Inoculant Carrier

Summary: Using controlled shear-rate testing ramps, this study investigates the rheological properties of carboxymethycellulose (CMC)/starch blends, with and without zinc oxide (ZnO). Viscosity decreased as the amount of starch increased and after adding 1% ZnO. The creep and recovery tests indicated that, with increasing starch content, there was a decrease in elasticity and the viscosity zero shear rate. The results also showed, in the temperature range between 25 and 70 °C, an inversion occurred in the elastic and viscous moduli behavior, obeying the Arrhenius equation. The addition of ZnO affects the viscoelastic behavior and the morphology of the blends. The best survival results were obtained for samples 50/50 and 60/40 wt% (CMC/starch).     

石油磺酸盐水溶液及其油/水平衡体系

应用ＥＳＲ法研究了石油磺酸盐水溶液及其油／水平衡 水溶液胶束的形成及其微观性质,结果表明,石油磺酸盐／３％正丁醇／０．３％,氯化十二烷平衡体系的有效临界胶束浓度远高于石油磺酸盐在３％正丁醇,０．３％氯内中的临界胶束浓度（ＣＭＣ）,发产生正比结果的原因。     

Influence of Hydrogen Peroxide on Disinfection and Soil Removal during Low-Temperature Household Laundry

In the Water, Energy and Waste Directive, the European Commission provides for the use of household washing programmes with lower temperatures (30–40 °C) and lower water consumption. However, low washing temperatures and the absence of oxidising agents in the liquid detergents, and their reduced content in powder detergents, allow biofilm formation in washing machines and the development of an unpleasant odour, while the washed laundry can become a carrier of pathogenic bacteria, posing a risk to human health. The aim of the study was to determine whether the addition of hydrogen peroxide (HP) to liquid detergents in low-temperature household washing allows disinfection of the laundry without affecting the properties of the washed textiles even after several consecutive washes. Fabrics of different colours and of different raw material compositions were repeatedly washed in a household washing machine using a liquid detergent with the addition of 3% stabilised HP solution in the main wash, prewash or rinse. The results of the antimicrobial activity, soil removal activity, colour change and tensile strength confirmed the excellent disinfection activity of the 3% HP, but only if added in the main wash. Its presence did not discolour nor affect the tensile strength of the laundry, thus maintaining its overall appearance.     

Isolation and characterization of microorganisms degrading nylon 4 in the composted soil

Two kinds of microorganisms, a bacterium (KT-1 strain) and a fungus (KT-2 strain), degrading nylon 4 (polyamide 4), which was easily prepared by the anionic ring-opening polymerization of 2-pyrrolidone, were isolated from the composted soil with the utilization of enrichment cultures and the culture using nylon 4 as a carbon source. KT-1 and KT-2 strains were identified as neighboring species to Stenotrophomonas sp. and Fusarium sp., respectively, by their morphological properties and the nucleotide sequences. These strains were confirmed to grow in the culture medium containing nylon 4 powders as a carbon source. In addition, nylon 4 film was decomposed in both mineral media containing KT-1 and KT-2 strains, respectively, and disappeared within two months. The MALDI TOF-MS analysis of nylon 4 recovered during the biodegradation test suggest that the isolated KT-2 strain recognize the acyllactam or carboxy chain end and degrade them or their neighboring amide bond.     

Preparation of 3‐aminopropyltriethoxy silane modified cellulose microcrystalline and their applications as flame retardant and reinforcing agents in epoxy resin

Cellulose microcrystalline (CMC), a linear polysaccharide with glucosidic bond, was successfully extracted from bamboo powder and modified by 3‐aminopropyltriethoxy silane coupling agent (KH550) to prepare KH550‐CMC. The prepared KH550‐CMC, in association with ammonium polyphosphate (APP), was introduced into epoxy resin (EP) by casting process to obtain flame retardant composites. The fire performance evaluation indicated that the presence of 10‐phr APP and 5‐phr KH550‐CMC in EP achieved the maximal LOI value of 28.9%, passed the UL‐94 V‐0 rating, and significantly decreased the peak heat release rate from 1055 kW/m² of neat EP to 286 kW/m². The improved fire performance is due to the improvement of dispersity of CMC in EP matrix and formation of better char layer, thus protecting the matrix effectively. Moreover, the introduction of KH550‐CMC could also partly eliminate the negative influence of flame retardants on the mechanical properties of EP composites due to the strengthening effect of CMC and better interfacial compatibility after modification with KH550.     

Determination of three kinds of banned drugs in milk powder by hybrid solid‐phase extraction purification combined with gas chromatography and mass spectrometry

A gradient clean‐up method for the quantification of five kinds of banned drugs (two hormones, two sedatives, and one chloramphenicol) in milk powder was developed. We used the combination of solid‐phase extraction purification with gas chromatography and mass spectrometry. Milk powder was initially hydrolyzed by β‐glucuronidase/arylsulfatase, and then the hydrolyzed solution was concentrated and purified using a C₈ and cation resin solid‐phase extraction column. To isolate hormones and chloramphenicol drugs, products from the previous step were diluted with methanol and further purified using a silica and diatomite solid‐phase extraction column. After derivatization, the drugs were analyzed by gas chromatography with mass spectrometry, and the hydrolyzed solution was diluted with 5% ammoniated methanol to purify sedatives before gas chromatography with mass spectrometry analysis. Results showed that after adding the banned drugs at concentrations of 0.3–10.0 μg/kg, the average recovery range was 78.2–97.3% with relative standard deviations of 5.3–12.5%. The limit of quantification of the banned drugs (S/N ≥ 10) was 0.3–5.0 μg/kg, whereas the limit of detection (S/N ≥ 3) was 0.1–2.0 μg/kg. The solid‐phase extraction gradient purification system was simple, rapid, and accurate, and could satisfy the detection requirements of hormone, sedatives, and chloramphenicol drugs when used together with gas chromatography and mass spectrometry.     

How does beta-cyclodextrin affect oxygen solubility in aqueous solutions of sodium perfluoroheptanoate?

The solubility of oxygen in aqueous solutions of sodium perfluoroheptanoate (NaPFHept) at different concentrations was measured at 310.15 K with an apparatus based on the saturation method. The effect of adding beta-cyclodextrin (betaCD) on the solubility of oxygen was also studied. Conductimetry measurements showed that the presence of betaCD in aqueous solutions of NaPFHept increases its critical micellar concentration (CMC). In the presence of betaCD (15 mM), the characteristic minimum of oxygen solubility observed at the CMC is shifted from 83 to 114 mM, and the curvature at the minimum is reduced to 64% of the value in the absence of betaCD. Chemical shift changes for the H5 protons of betaCD, recorded as functions of the initial concentration of NaPFHept, point to the formation of a relatively strong 1:1 inclusion in betaCD of the perfluoroheptanoate anion. Hence, it is suggest that the effect of adding betaCD on the solubility of oxygen cannot be accounted for only by the perfluoroheptanoate anion inclusion in betaCD, but has to be ascribed to the direct influence of this inclusion complex on disrupting the aggregation process reducing the increase of oxygen solubility after the CMC value.