毒死蜱人工抗原的合成及多克隆抗体制备

由毒死蜱与3-巯基丙酸在碱性条件下反应,合成了毒死蜱半抗原。然后通过碳二亚胺法将毒死蜱半抗原分别与牛血清白蛋白(BSA)和鸡卵清白蛋白(OVA)共价偶联,得到了免疫抗原和包被抗原。用免疫抗原免疫兔子获得了高效价的多克隆抗体,抗血清效价达到了1:160000。通过试验确立了毒死蜱标准曲线,检测限为0.5μg.L-1,抑制中浓度I50为18.2μg.L-1,检测线性范围为1.8～1000μg.L-1。     

溴氰菊酯人工抗原及多克隆抗体制备

以二溴菊酸和4-[(4-硝基苯)氧基[苯甲醛为原料经4步反应合成了溴氰菊酯半抗原1-氰基[4-(4-氨基苯)苯基]甲基-2,2-二甲基3-(2',2'-二溴乙烯基)环丙烷羧酸酯;用重氮化法将溴氰菊酯半抗原分别与牛血清白蛋白(BSA)和卵清白蛋白(OVA)相偶联制备免疫抗原和包被抗原,紫外吸收法估算偶联比分别为11:l和8:1;以BSA偶联物作免疫抗原免疫日本大耳白兔制备溴氰菊酯多克隆抗体,间接非竞争ELISA法测定两个抗血清效价分别为100000和80000,间接竞争ELISA法测定抗体特异性结果表明所制备的抗体测定溴氰菊酯的IC50值为0.16 mg/L,与其他供试农药的交叉反应率均≤1%.制备的溴氰菊酯人工抗原和多克隆抗体为研究建立溴氰菊酯农残免疫快速测定方法奠定了基础.     

10-羟基喜树碱水溶性磷酰化衍生物的合成

以10-羟基喜树碱(HCPT)为原料,吡啶为溶剂,经过磷酰化、酯化、水解三步反应合成了全新的水溶性磷酰化衍生物. 得到的较佳工艺条件为：磷酰化反应三氯氧磷与HCPT的投料摩尔比2:1(相对0.01 mol HCPT),反应温度-10℃,搅拌下反应时间30 min;酯化反应乙醇与HCPT的投料摩尔比6:1,反应温度10℃,搅拌下反应时间1.5 h;水解反应保持体系pH<5.0. ODS制备柱分离得到产物,总收率为30.0%.     

对氯甲基苯乙烯及其聚合物的合成研究

以苯乙醇为起始原料,经过取代、氯甲基化和消除反应制备对氯甲基苯乙烯,并通过自由基聚合反应合成聚对氯甲基苯乙烯。通过实验得到消除反应的最佳反应条件为:搅拌速率为12 r/min,反应温度35℃,反应时间160 min;自由基聚合的最佳反应条件为:反应温度70℃,反应时间为13 h,搅拌速率17 r/min。     

5,5'-亚甲基二水杨酸的合成研究

用33%硫酸作为催化剂制备了5,5'-亚甲基二水杨酸,并通过正交实验确定了合成该化合物的最佳工艺条件:水杨酸与甲醛按摩尔比1:0.58投料,反应温度95℃,反应时间12 h.通过红外光谱对所得产物进行了表征.     

含酰亚胺结构聚酰胺的合成研究

通过偏苯三酸酐与11-氨基十一酸反应,制备了酰亚胺酸,经与己二胺聚合合成了含酰亚胺结构的聚酰胺,详细探讨了反应时间、脱水时间、脱水温度、投料比等反应条件对聚合物结构的影响,确定了最佳合成条件.合成产物具有比尼龙11高的耐热温度.     

乙酰氧肟酸的合成研究

研究了盐酸羟胺与乙酸乙酯反应制备乙酰氧肟酸的合成工艺,确定了投料配比、反应时间、反应温度等工艺条件.并对反应的溶剂体系进行了研究,找到了合适的溶剂体系,并确定了其最佳用量.所得产品产率84%,纯度97%.     

乙酰氧肟酸的合成研究

研究了盐酸羟胺与乙酸乙酯反应制备乙酰氧肟酸的合成工艺,确定了投料配比、反应时间、反应温度等工艺条件.并对反应的溶剂体系进行了研究,找到了合适的溶剂体系,并确定了其最佳用量.所得产品产率84%,纯度97%.     

盐酸头孢替胺合成研究

在盐酸头孢替安粗品生产过程中,关键反应为7-DMTA的缩合反应、ATC.HCL的缩合反应以及盐酸头孢替安粗品的合成反应。通过反应过程中溶剂的选择、反应投料比、反应时间等参数的调整,最终确定可以工业生产的工艺路线和条件。     

正交优化盐酸倍他司汀的合成工艺

以2-甲基吡啶为原料,经四步反应合成盐酸倍他司汀。通过正交实验,确定最佳合成的工艺条件为:2-乙烯基吡啶与甲胺的投料比为1∶1.5,反应时间为8h,反应温度为105℃,收率为86.8%,其中投料比为影响产率的主要因素。最佳工艺为A2B2C3,产物结构经熔点、MS、1HNMR谱确证。     

Comparison of the Crystals Obtained by Precipitation of CL‐20 with Different Chemical Purity

The precipitation of CL‐20 with different chemical purity is presented herein. Studies have shown that the first crystallization of the crude CL‐20 does not allow achieving the expected polymorphic purity and slightly increases chemical purity. Further precipitation processes result in gradual increase of the chemical purity about 1–2 % and in the improvement of the properties of crystals, i.e. density, polymorphic purity, and sensitivity to friction. This paper attempts a preliminary purification of the crude CL‐20 with columns filled with activated charcoal. A material of high purity, obtained by this process, was used in the process of precipitation. As a result of the crystallization a sample of CL‐20 was obtained with high chemical purity of 99.5 % and significantly reduced sensitivity to friction (128 N) and to impact (4 J). Additionally, samples of CL‐20, recovered from the filtrate after crystallization with a chemical purity of about 88 %, were purified on columns filled with activated charcoal. In this process a significant amount of impurities was removed and the purity was increased to 96 %.     

Ring-opening polymerization of ?-caprolactone by poly(propyleneglycol) in the presence of a monomer activator

The ring-opening polymerization of ?-caprolactone (CL) was induced by using polypropylene glycol (PPG) as an initiator in the presence of the monomer activator HCl·Et₂O to synthesize triblock copolymers composed of PPG and poly(?-caprolactone) (PCL). The degree of CL conversion and the molecular weight of PCL increased linearly with the polymerization time or with the feed ratio of CL to PPG in the presence of HCl·Et₂O in CH₂Cl₂ at 25 °C. The PCLs obtained had molecular weights close to the theoretical values calculated from the CL:PPG molar ratios and exhibited monomodal GPC curves with narrow polydispersity indexes. The apparent rate constant (k_app) for the polymerization of CL activated by HCl·Et₂O was greatly affected by the ratio of HCl·Et₂O/PPG. The activation energy for the polymerization of CL in this system was estimated to be 49.8 kJ/mol K. We successfully prepared PPG and PCL triblock copolymers using this activated monomer mechanism.     

Thermal properties and biodegradability of the copolymers of l-lactide, ?-caprolactone, and ethylene glycol oligomer with maleate units and their crosslinked products

Copolymers of l-lactide (LLA), ?-caprolactone (CL), and ethylene glycol oligomer (EGO) were synthesized by ring-opening copolymerization of CL and LLA initiated by EGO at the LLA/CL molar ratios of 7/3, 5/5, and 3/7. The resulting viscous ternary copolymers (PLCE) with weight average molecular weight (M_w) ca. 3000 were reacted with maleic anhydride to give unsaturated group-containing copolymer (PLCEM) with M_w 6000-8000. The degree of unsaturation of PLCEM was 0.3-0.6 per one EGO block. The PLCEM was cured with benzoyl peroxide (BPO) to give a viscoelastic soft material insoluble in any solvent. The DSC analysis of the copolymers revealed that all the copolymers are amorphous materials having a glass transition temperature (T_g), which increased with increasing LLA/CL ratio. The crosslinked PLCEM showed a higher T_g than the corresponding PLCE and PLCEM. The crosslinked PLCEM showed good biodegradability, when measured by a BOD method using activated sludge.     

Nanostructured Energetic Composites of CL‐20 and Binders Synthesized by Sol Gel Methods

Monolithic energetic gels were prepared in acetone by separately cross‐linking the single precursors, glycidyl azide polyol (GAP polyol polyol), nitrocellulose (NC, 12% N), and tris(hydroxymethyl)nitromethane (THMNM) and the mixed precursors (GAP polyol+NC) and (GAP polyol+THMNM) with hexamethylene diisocyanate (HDI). THMNM functions as a chain extender. The synthesis conditions were optimized according to precursor mass ratio, cross‐linking agent, solvent, catalyst concentration, and containers with various surface‐to‐volume ratios. The concentrations of reactants and cure catalyst are the most important factors. The composite energetic materials with a high degree of homogeneity were synthesized by trapping hexanitrohexazaisowurtzitane (CL‐20) on the nano scale in the energetic polymer gels using sol gel processing with a modified freeze‐drying procedure. Loadings up to 85%, 93%, and 90% by weight of CL‐20 yielded, respectively, monolithic gels for GAP/HDI, NC/HDI, and THMNM/HDI. 90% CL‐20 can be loaded into gels of the mixed precursors of (GAP polyol+NC) and (GAP polyol+THMNM). The energetic gels and composites were characterized using FT‐IR spectroscopy, DSC, SEM, and sensitivity to drop weight impact. The sensitivity of CL‐20 is reduced in the energetic nanocomposites.     

Preparation of methoxy poly(ethyleneglycol)-block-poly(caprolactone) via activated monomer mechanism and examination of micellar characterization

Summary The polymerization of ε–caprolactone (CL) in the presence of HCl·Et₂O via activated monomer mechanism was performed to synthesize diblock copolymers composed of methoxy polyethyleneglycol (MPEG) and poly(ε–caprolactone) (PCL). The obtained PCLs had molecular weights close to the theoretical values calculated from the CL to MPEG molar ratios and exibited monomodal GPC curves. We successfully prepared MPEG and PCL diblock copolymers by activated monomer mechanism. The micellar characterization of MPEG-PCL diblock copolymers in an aqueous phase was carried out by using NMR, dynamic light scattering, AFM and fluorescence techniques. The diblock copolymers formed micelles with a critical micelle concentration (CMC) ranging 2.07×10^-2–1.16×10^-3 mg/mL depended on the block lengths of diblock copolymers. The diameters of micelles, measured by dynamic light scattering, were 100–250 nm. Most micelles exhibited a spherical shape in AFM.     

Polymerization of Lactams: 57. G.l.c. and n.m.r. analysis of the anionic copolymers of 2-pyrrolidone with 6-caprolactam and 8-octanelactam

The activated anionic copolymerization of 2-pyrrolidone (PD) with 6-caprolactam (CL) or 8-octanelactam (OL) proceeds even above the ceiling temperature for PD homopolymerization. At high temperatures, the copolymerizations are accompanied by the depolymerization of PD sequences, which is more pronounced with the copolymers with CL. The copolymers obtained probably exhibit a constitutional heterogeneity and contain considerable amounts of low-molecular weight fractions. This may be the reason why the content of comonomers in the prepared copolymers determined by g.l.c. did not agree with that found by ¹H n.m.r. or ¹³C n.m.r. spectroscopy. The copolymers with CL had in part a block structure and also an alternating character, depending on temperature and polymerization time, while random copolymers were obtained at high temperatures. The copolymers with OL tended mostly to alternation.     

Rate of the activated anionic polymerisation of ε-caprolactam onto an isocyanate bearing polypropylene in the melt

This paper concerns the rate of the activated anionic polymerisation of ε-caprolactam (CL) onto 3-isopropenyl-α,α-dimethylbenzyl isocyanate bearing PP (PP-g-TMI) in the melt to form a graft copolymer with PP as backbone and PA6 as grafts. The polymerisation was catalysed by sodium ε-caprolactam (NaCL). The PP-g-TMI/NaCL/CL polymerisation system being heterogeneous, the polymerisation was carried out in a batch mixer. Emphasis was placed on the effects of temperature and the concentrations of NaCL and the isocyanate group in the form of PP-g-TMI on the polymerisation rate. Results suggested that if the polymerisation is to be carried out by a reactive extrusion process whose mean residence time is less than a few minutes, it is recommended that the polymerisation temperature be higher than 220 °C. Moreover, the molar ratio between NaCL and CL should be higher than 0.5 and at the same time that between the isocyanate group in the form of PP-g-TMI and NaCL, should be smaller than 4.     

Development of a flow injection chemiluminescent assay for the quantification of lipid hydroperoxides

An automated flow injection chemiluminescence (FICL) system for measuring lipid hydroperoxide (LOOH) concentrations in oils was developed. Initially, a crude oil-in-water emulsion (formed by mixing solvent-diluted oil with the aqueous-based CL compound, luminol, and the catalyst for the reaction, cytochrome c) was tested. The assay was rapid (60 samples per hour), reproducible (CV no greater than 10%, n=3) and had a low sample requirement (1 mg of oil) because of its high sensitivity (0.5 nmol LOOH). CL intensity was influenced by the amount and type of oil under analysis. Owing to these factors, quantitative data were attainable only with a uniform oil concentration and with a calibrant derived from an oil equivalent to that under analysis. This method yielded quantitative data in good agreement with an iodometric titration assay for LOOH (r=0.9204). A refinement of the first method consisted of replacing the luminol and cytochrome c CL compounds with lucigenin, resulting in an assay insensitive to α-tocopherol. A monophasic reaction solution was devised to remove the effect of turbidity; however, the CL signal was still influenced by oil type. Therefore, quantitative data were still attainable only when the same type of oil was used for calibration.     

Copolymers of ε-caprolactam and polypropylene oxide via anionic polymerization: synthesis and properties

Copolymers with an elastic polypropylene oxide (PPO), middle block in the main chain of poly(ε-caprolactam) were synthesized via activated anionic ring opening polymerization of ε-caprolactam (CL) in the presence of a basic initiator sodium salt of CL (Na-CL) and effective bifunctional polymeric activators (PACs). By varyng the molecular weight, two types of PACs were synthesized based on carbamoyl derivatives of hydroxyl terminated PPO with isophorone diisocyanate and were blocked with CL. The formation of copolymers has been confirmed by proton nuclear magnetic resonance spectroscopy (¹H–NMR) and Fourier transform infrared spectroscopy (FT-IR). The influence of the molecular weight of the PACs, the CL/PAC ratio and polymerization conditions on the conversion, intrinsic viscosity and polymerization kinetics, was investigated. The calorimetric, wide-angle X-ray diffraction (WAXD), thermogravimetric analysis (TGA), notched impact test and dynamic mechanical thermal analysis (DMTA) were performed to estimate the influence of the composition ratio and the type of PACs on the physical, thermal, and mechanical properties of the copolymers. The use of the synthesized PACs reduced the polymerization time to several minutes. The copolymers showed improved impact resistance up to more than two times higher than those of the polyamide 6 (PA-6) homopolymer, without significant changes in their high melting temperatures.     

Novel Graphene Foam Microporous Layers for PEM Fuel Cells: Interfacial Characteristics and Comparative Performance

The microporous layer (MPL) provides many beneficial properties for performance improvement of H₂ PEM fuel cells, particularly with respect to water management and two‐phase (gas/liquid) flow dynamics. However, the interface between the catalyst layer (CL) and MPL could be a source of additional overpotential losses due to poor electronic conductivity and/or mass transfer limitations. This is particularly important for low loading CLs which may suffer from spatial disconnect with the micro‐scaled features of conventional MPLs. In an effort to better understand the factors influencing the MPL|CL interface, the conventional carbon MPL is comparatively studied with respect to three alternative layers: graphene foam, perforated graphitic sheet and perforated stainless steel. The graphene foam shows beneficial interfacial properties that contribute to electrode kinetic and ohmic improvements during polarization. This can be attributed to the graphene's ability to conform at local length scales due to its unique flake‐like structure (achieved upon compression), an ability to intimately adhere to the CL and the layer's superior conductivity. Further investigation through single cell performance tests supports the application of the graphene foam as an MPL alternative. The results also highlight the interplay of various factors that influence the MPL|CL interface and ultimately the overall polarization performance, such as: morphology, conductivity, connectivity, compression and adhesive effects between layer components.