Synthesis and characterization of α‐butyl‐omega‐{3‐[2‐hydroxy‐3‐(N‐methyl‐N‐hydroxy‐ ethylamino)propoxy]propyl}polydimethylsiloxane

A novel synthesis path for the monotelechelic polydimethylsiloxane with a diol‐end group, α‐butyl‐omega‐{3‐[2‐hydroxy‐3‐(N‐methyl‐N‐hydroxyethylamino)propoxy]propyl}polydimethylsiloxane, is described in this article. The preparation included three steps, which were anionic ring‐opening polymerization, hydrosilylation, and epoxy addition. The structure and polydispersity index of the products were analyzed and confirmed by FTIR, ¹H NMR, ¹³C NMR, H? H, and C? H. Correlated Spectroscopy and gel permeation chromatography. The results demonstrated that each step was successfully carried out and the targeted products were accessed in all cases. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

几个含噻二唑环芳甲酰基脲的合成及生物活性

通过2-氨基-5-(3-吡啶基)-1,3,4-噻二唑与取代苯甲酰基异氰酸酯反应,得到相应的芳甲酰基脲:N-[5-(3-吡啶基)-1,3,4-噻二唑-2-基]-N′-(2-氯苯甲酰基)脲(Ⅲa)、N-[5-(3-吡啶基)-1,3,4-噻二唑-2-基]-N′-(2-溴苯甲酰基)脲(Ⅲb)、N-[5-(3-吡啶基)-1,3,4-噻二唑-2-基]-N′-(4-溴苯甲酰基)脲(Ⅲc)、N-[5-(3-吡啶基)-1,3,4-噻二唑-2-基]-N′-(2-甲基苯甲酰基)脲(Ⅲd)和N-[5-(3-吡啶基)-1,3,4-噻二唑-2-基]-N′-(4-三氟甲基苯甲酰基)脲(Ⅲe),收率分别为69.5%、67.2%、73.1%、66.8%和71.6%.产物的结构经红外光谱、核磁共振氢谱、质谱与元素分析表征.并对目标化合物进行了植物生长调节活性测试,初步的测试结果表明,目标化合物在10 mg/L表现出一定程度的生长素活性和较好的细胞分裂素活性,其中Ⅲc和Ⅲe的细胞分裂素活性超过40%.     

水溶性噻二唑衍生物的合成及其摩擦学性能研究

合成一种新型水溶性噻二唑衍生物,采用红外光谱仪对其结构进行表征,采用SRV摩擦磨损试验机考察其在三乙醇胺水溶液中的摩擦学性能,采用表面轮廓仪及扫描电子显微镜观察磨斑表面形貌。SRV摩擦实验结果表明,该添加剂能显著改善三乙醇胺基础液的抗磨减摩性能,并能有效避免疲劳磨损;XPS结果显示,添加剂通过与摩擦副表面的摩擦反应生成FeS及Fe2O3等反应膜,起到极压抗磨的效果;同时该添加剂还具有很好的抑制铜片腐蚀的性能,是一种环境友好的多功能润滑添加剂。     

基于AT89C52的便携式甲醛检测仪设计

为了能够准确测量室内和一些特殊环境甲醛浓度,以单片机AT89C52为主控核心,采用电化学CH2O甲醛传感器为数据采集模块,设计了一种用于室内及一些特殊环境中甲醛浓度检测装置。     

无溶剂干法固相合成1,3,4-噁二唑衍生物

以对称二酰基肼和P2O5为原料用无溶剂干法固相合成了一系列1,3,4-噁二唑衍生物,研究了取代基的种类和取代位置对产物收率的影响,并采用荧光发射光谱和紫外-可见吸收光谱测定了其光物理化学性能。结果表明,在所合成的衍生物中,氟原子在对位取代时产率最高;强吸电性的硝基,使荧光发射波长和紫外-可见吸收波长发生明显的红移。此法避免使用大量有机溶剂,节约资源、减少了环境污染。     

具有"开-关"特性的pH荧光探针DPVF的合成与表征

合成并表征了{4-[2-(4-氟苯基)-乙烯基]-苯基}-二甲基胺(DPVF).结果表明,DPVF(10.0 μmol·L-1)的水∶乙醇=1∶1(体积比)溶液的紫外可见吸收强度对pH值(7.02～2.22)变化灵敏,荧光强度对pH值(7.02～1.66)变化灵敏.荧光增强阶段是氟原子质子化,荧光减弱阶段是氟原子与氮原子同时质子化,氮原子与氟原子都是pH功能基.该化合物显示了"开-关"荧光发射性能,可应用于荧光分子开关;同时又是一个很好的pH荧光探针,检测pH值范围为7.02～1.66,pH值检测最高灵敏度为ΔpH=0.04.     

Comparison of OWAS,RULA and REBA for assessing potential work-related musculoskeletal disorders

This study compared three representative observational methods for assessing musculoskeletal loadings: Ovako Working Posture Analysis System (OWAS), Rapid Upper Limb Assessment (RULA), and Rapid Entire Body Assessment (REBA). The comparison was based on 209 cases of upper-body musculoskeletal disorders (MSDs) diagnosed by medical doctors. The most awkward/stressful posture in each participant's tasks was assessed using these techniques. Postural loadings were rated more highly by the RULA than by the OWAS and REBA (p < 0.01). The chi-square test and logistic regression analysis showed that only RULA grand score and action level, and REBA action level were associated with MSD work-relatedness (p < 0.01, p < 0.05, and p < 0.05, respectively). The percentage concordant values of the logistic model for the RULA grand score and action level were 52.4% and 44.8%, respectively, while the percentage concordant value for the REBA action level was 22.1%. Therefore, the RULA may be the best system for estimating the postural loads and work-relatedness of MSDs.Relevance to industryWork-related musculoskeletal disorders are the leading cause of workplace disability in the developed countries. For preventing the disorders, quantification of musculoskeletal loads is required.     

保域上矩阵可交换｛1｝-逆的线性映射

设F是一个特征不为2且至少含有5个元素的域.令Mn(F)为F上的n×n全矩阵代数.刻画了Mn(F)上保持矩阵可交换{1}-逆的线性映射的形式.利用保幂等结论证明了f为Mn(F)上的保持矩阵可交换{1}-逆的非零线性映射,当且仅当存在P∈GLn(F),使得f(A)=εPAP-1,A∈Mn(F),ε=±1∈F;或者存在P∈GLn(F),使得f(A)=εPAtP-1,A∈Mn(F),ε=±1∈F.     

The associations between genetics,salt taste perception and salt intake in young adults

Food liking is one of the main determinants of food intake. Salt taste perception and preference, that play a role in liking of salt, may be genetically determined, although research in humans is scarce. The aim of this study was to explore the associations between genetics, salt taste perception, preference, self-reported salt habit and intake. The participants were young (18–35 years) and healthy adults (32 males and 63 females). Salt taste thresholds were determined with British Standard ISO3972:2011 methodology and salt taste preference by ratings of saltiness and pleasantness of tomato soup with salt concentrations reflecting salt content in foods. Self-reported salt habit was determined by asking participants how salty they usually eat their food and salt intake with two 24-hour 5-step multiple pass recalls. Genotyping for variants in the SCNN1B rs239345 and TRPV1 rs8065080 was performed. Participants homozygous for the minor allele of the rs8065080 had lower ratings of saltiness (p = 0.008) and higher ratings of pleasantness of soup (p = 0.027) when compared to major allele carriers. Preference for salt in soup was associated with salt habit (p = 0.003) and participants with high salt preference had higher salt intake compared to those with low salt preference (2236 ± 261 vs. 1543 ± 107 mg/1000 kcal, p = 0.017). TRPV1 rs8065080 may play a role in salt taste perception and preference, which should be confirmed in a larger sample size study. Hedonic appeal of salty food should be considered when providing personalised advice to change this behaviour.     

Simultaneous biohydrogen (H2) and bioplastic (poly-β-hydroxybutyrate-PHB) productions under dark,photo, and subsequent dark and photo fermentation utilizing various wastes

The present study is focused on bio hydrogen (H₂) and bioplastic (i.e., poly-β-hydroxybutyrate; PHB) productions utilizing various wastes under dark fermentation, photo fermentation and subsequent dark-photo fermentation. Potential bio H₂ and PHB producing microbes were enriched and isolated. The effects of substrate (rice husk hydrolysate, rice straw hydrolysate, dairy industry wastewater, and rice mill wastewater) concentration (10–100%) and pH (5.5–8.0) were examined in the batch mode under the dark and photo fermentation conditions. Using 100% rice straw hydrolysate at pH 7, the maximum bio H₂ (1.53 ± 0.04 mol H₂/mol glucose) and PHB (9.8 ± 0.14 g/L) were produced under dark fermentation condition by Bacillus cereus. In the subsequent dark-photo fermentation, the highest amounts of bio H₂ and PHB were recorded utilizing 100% rice straw hydrolysate (1.82 ± 0.01 mol H₂/mol glucose and 19.15 ± 0.25 g/L PHB) at a pH of 7.0 using Bacillus cereus (KR809374) and Rhodopseudomonas rutila. The subsequent dark-photo fermentative bio H₂ and PHB productions obtained using renewable biomass (i.e., rice husk hydrolysate and rice straw hydrolysate) can be considered with respect to the sustainable management of global energy sources and environmental issues.