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71.
72.
The paper first provides, for Latin America and the Caribbean, country-specific synthetic quantitative measures of the degree of adoption of governance reforms in the electricity sector, focusing on four key dimensions (market structure, private sector participation (PSP), regulatory autonomy and operational organization). These measures are then correlated with standard policy performance outcomes measures. The findings suggest that, the reforms, considered jointly, were statistically significantly associated with higher technical and process quality but not with social or service improvements. Considered individually, increased regulatory autonomy enjoyed the highest positive correlation with desirable outcomes, but PSP has no significant correlation with any of the outcomes. In sum, as of 2018, governance reforms, considered jointly, had still not delivered on some promised payoffs, notably in addressing energy poverty, although the sensitivity analysis suggests that, for some indicators, the relationships are stronger for larger than for smaller countries. 相似文献
73.
《Contact lens & anterior eye》2020,43(4):338-344
PurposeTo compare the sensitivity of two genotypes of P. aeruginosa to various disinfectant solutions and analyze the attached bacteria on worn cosmetic contact lenses (cosCLs).MethodsIn this prospective study, healthy volunteers wore etafilcon (brown), nelfilcon (gray), or hilafilcon (black) cosCLs and microbial adhesion analysis was performed. A rub-off test determined pigment dislodgement. Disinfectant sensitivity to Optifree Replenish (Alcon), Optifree Pure Moist (Alcon), Renu Fresh (Bausch & Lomb), and AoSept Plus (Ciba Vision) was tested at various disinfection times and compared between various genotypes and Type III secretion (T3S) system mutants.ResultsOf the 1152 cosCLs collected, 364 were culture positive (32%). The highest rate of culture-positive lens was hilafilcon (chi square, P = 0.0001). Hilafilcon also had a significantly greater number of isolates than etafilcon (P < 0.0001). Hilafilcon was the only lens to fail the rub-off test. Cytotoxic strains were significant more resistant to Renu Fresh than were invasive strains, even at 100% of recommended disinfection time (P = 0.0005). Of the tested disinfectants, Renu Fresh was significantly less effective in killing both genotypes of P. aeruginosa compared to AoSept Plus at all time points (25%, 50%, 75%, and 100% recommended disinfection time, P = 0.0001, 0.0001, 0.0005, and 0.0005, respectively). When the T3S system was dysfunctional, mutant strains were all susceptible to disinfectants (P = 0.0001 for both invasive and cytotoxic strains).ConclusionPseudomonas species is commonly found on cosCLs of asymptomatic individuals. Wearers of cosCLs that dislodge pigments may be predisposed to microbial contamination. Cytotoxic strains are more resistant to disinfectant solutions, especially to Renu Fresh. P. aeruginosa disinfectant resistance requires a functional T3S system. 相似文献
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75.
《Ceramics International》2020,46(11):18623-18631
Low haze and anti-reflective glass has high potential applications in automobile and optoelectronic fields. Etching is a novel and effective method to fabricate gradient refractive index anti-reflective layer on glass surface. However, the gradient layer on glass surface prepared by the etching method usually characterizes rough porous structure, and the structural defect results in high haze and low abrasion resistance to restrict its applications. In this paper, a hydrothermal etching method has been explored to prepare anti-reflective glass. It has demonstrated to be a new and facile method successfully to tailor the porous nanostructure of gradient refractive index layer and largely decrease the haze of the glass, by adding complex compound in the etching solution. Compared with the etching solution containing NaOH, adding the complex compound of C6H5Na3O7 in the etching solution has the advantage to overcome the defects. The grain diameter of the graded porous anti-reflective film decreases from ~63 nm to ~18 nm, the etched film thickness increases from 0.44 μm to 1.55 μm, the haze decreases drastically from 23.76% to 1.00%, the reflectivity decreases from 5.88% to 1.08% and the abrasion resistance greatly increases. However, when changing the complex compound from C6H5Na3O7 to Na2HPO4, the haze is 23.44% and has no effect on decreasing haze. Structural characterizations show that the grain size in the porous gradient layer can be easily tailored by changing the ion radius of complex anion in the etching solution, and the optical properties can be controlled. The paper provides new insights into the nanostructures and the preparation approach of anti-reflective glass. 相似文献
76.
为了研究缓蚀剂组分及添加条件对发射药性的影响,设计并制备了一种含新型有机硅的缓蚀剂材料;采用烧蚀管法,对比石蜡+TiO2型缓蚀剂,研究了新型有机硅缓蚀剂的静态降烧蚀效果;采用密闭爆发器研究了不同缓蚀剂添加条件对高能硝胺发射药点火和燃烧性能的影响;采用14.5mm弹道枪和壁温测试装置,研究不同缓蚀剂添加条件对膛壁温度、内弹道性能和枪口烟雾的影响。结果表明,采用含新型有机硅的缓蚀剂,降烧蚀效果更为显著;随着缓蚀剂添加量的增加,压力峰值、弹丸初速也会产生小幅下降,但总体影响幅度较小;添加缓蚀剂后,射击过程膛壁峰值温度显著下降,下降幅度随着缓蚀剂添加量的增加而增加,在缓蚀剂质量分数为3%时,对身管壁温降低幅度可达17.1%,且产生的枪口烟雾量较少;在缓蚀剂质量分数为5%时,缓蚀剂添加过量,枪口产生较大烟雾。该缓蚀剂及添加条件有望应用于低烧蚀发射药配方中。 相似文献
77.
在1400℃下,将平均尺寸φ15 mm?10 mm的石灰块投入CaO?SiO2?FeO及CaO?SiO2?FeO?P2O5两组渣系中,研究了静态条件下石灰在两组渣系中的溶解行为。结果表明,两组渣系在反应界面周围形成四个区域,即基体渣层、C2S渗透层、铁酸钙渗透层和石灰层。渗透层为石灰中的Ca2+与液渣中的Fe2+相互渗透所形成的一个多相共存区域,存在致密固相层影响石灰的溶解。渗透层中的铁酸钙层逐渐被C2S层取代,C2S层厚度不断增加最终溶解于液相渣中。5~60 s两组渣系石灰溶解速度相近,60~80 s含磷渣系石灰溶解速度显著加快。当渣中加入P2O5时,磷会固溶于C2S中形成C2S?C3P固溶体层,该层的形成会排挤FeO进入渣中,提高渣的渗透能力,加速石灰溶解。 相似文献
78.
79.
简述了全球及我国环氧丙烷产业的生产及供需现状;对环氧丙烷在聚醚多元醇、丙二醇/碳酸二甲酯、丙二醇醚及其酯类等领域的应用进行了分析;并对环氧丙烷生产技术进行了比较,提出了发展建议。 相似文献
80.
Following the success of Auranofin as an anti-arthritic drug, search for novel gold drugs has afforded a large number of [L−Au(PPh3)] complexes that exhibit notable salutary effects. Unlike Au(III)-containing species, these gold complexes with {Au(PPh3)}+ moiety are stable in biological media and readily exchange L with S- and Se-containing enzymes or proteins. Such exchange leads to rapid reduction of microbial loads or induction of apoptotic cell death at malignant sites. In many cases the lipophilic {Au(PPh3)}+ moiety delivers a desirable toxic L to the specific cellular target in addition to exhibiting its own beneficial activity. Further research and utilization of this synthon in drug design could lead to novel chemotherapeutics for treatment of drug-resistant pathogens and cancers. 相似文献