Synthesis and antifungal activity of 2H-1,4-benzoxazin-3(4H)-one derivatives

A series of 2-alkyl-2H-1,4-benzoxazin-3(4H)-ones (4a-l) was easily synthesized by two-step process involving O-alkylation of 2-nitrophenols with methyl 2-bromoalkanoates and next “green” catalytic reductive cyclization of the obtained 2-nitro ester intermediates (3a-l). Further, 6,7-dibromo (5a-c) and N-acetyl (6) derivatives were prepared by bromination and acetylation of unsubstituted 2-alkyl-2H-1,4-benzoxazin-3(4H)-ones (4a-c). The novel compounds (3a-l, 4d-l, 5a-c and 6) were fully characterized by spectroscopic methods (MS, ¹H and ¹³C NMR). 2-Alkyl-2H-1,4-benzoxazin-3(4H)-ones (4a-l, 5a-c and 6) were screened for antifungal activity. Preliminary assays were performed using two methods: in vitro against seven phytopathogenic fungi—Botrytis cinerea, Phythophtora cactorum, Rhizoctonia solani, Phoma betae, Fusarium culmorum, Fusarium oxysporum and Alternaria alternata—and in vivo against barley powdery mildew Blumeria graminis. The tested compounds displayed moderate to good antifungal activity at high concentration (200 mg L^?1). The most potent compounds were 2-ethyl-2H-1,4-benzoxazin-3(4H)-one (4a), 2-ethyl-7-fluoro-2H-1,4-benzoxazin-3(4H)-one (4g) and 4-acetyl-2-ethyl-2H-1,4-benzoxazin-3(4H)-one (6), which completely inhibited the mycelial growth of seven agricultural fungi at the concentration of 200 mg L^?1 in the in vitro tests. Moreover, 2-ethyl-2H-1,4-benzoxazin-3(4H)-one (4a) and 4-acetyl-2-ethyl-2H-1,4-benzoxazin-3(4H)-one (6) were also screened for antifungal activity at concentrations of 100 mg L^?1 and 20 mg L^?1. In the concentration of 100 mg L^?1, the N-acetyl derivative (6) completely inhibited the growth of three strains of fungi (F. culmorum, P. cactorum and R. solani), while 2-ethyl-2H-1,4-benzoxazin-3(4H)-one (4a) completely inhibited only R. solani strain. At the concentration of 20 mg L^?1, compound 6 showed good activity only against P. cactorum strain (72%).     

Nano-textured polysilicon solar absorption films

Nano-textured polysilicon (poly-Si) solar absorption films are to be applied to the solar receiver of solar thermal electricity Stirling engine. These films were fabricated by deposition of hydrogenated amorphous silicon films (a-Si:H) into poly-Si films, using the pulse-wave modulation plasma and furnace annealing of the a-Si:H films. This is followed by wet etching of poly-Si films into nano-textured structures. The films are then coated with a-SiN_x:H films as the antireflection and protection layers. It was observed that increasing the pulsed plasma turn-on (t_on) time leads to deposition of less dense a-Si:H film with high hydrogen content and void density. This results in films having low dielectric constant and refractive index, and high optical bandgap. Less-dense a-Si:H film can be transferred into large grain size poly-Si film, using annealing. Also, highly rough nano-textured surface structure can be produced, by etching. The denser a-Si:H film, large grain size poly-Si film, and nano-textured surface poly-Si film can enhance the absorbance of sunlight and reduce the emissivity of far infrared light. The nano-textured poly-Si film coated with an a-SiN_x:H layer can effectively increase the absorbance of sunlight to approximately 85% and reduce the emissivity of far infrared light to 49%. The nano-textured poly-Si/a-SiN_x:H films can be used as efficient solar absorption films for solar thermal electricity Stirling engine.     

酸性红R在UV-蒙脱土KSF-H_2O_2体系中光降解行为研究

以紫外杀菌灯(波长为254nm)为光源,研究了酸性红R在由蒙脱土KSF和H2O2组成的类Fenton体系中的光降解行为,研究了反应体系pH、H2O2浓度对偶氮染料酸性红R光催化降解的影响,分析了酸性红R的光降解动力学规律。结果表明:对于100mg/L的酸性红R,在pH为3.0、66mg/L的H2O2和质量浓度为1g/L的蒙脱土条件下,在UV/类Fenton体系可以获得较高的反应速率,经50min的光照,酸性红R的光降解率为87.2%;而在类Fenton体系中的光降解率只有56%左右,可见UV对类Fenton体系有明显的协同作用;酸性红R的光降解动力学规律符合Langmuir-Hinshelwood方程,反应速率常数为1.82mg/(L·min)。     

氧化改性活性炭纤维吸附材料制备及其性能研究

目的 以不同浓度的双氧水溶液对活性炭纤维进行氧化改性,制备SO₂、NOx腐蚀气氛吸附材料。方法采用红外光谱、X射线衍射仪、X射线光电子能谱仪等表征方式,揭示双氧水改性对活性炭纤维孔隙结构、表面物理化学性质、吸附性能的影响,并将装有吸附材料的防护包装贮存于湿热海洋气候环境中,验证腐蚀气氛控制效果。结果 双氧水改性活性炭纤维后,其表面官能团未发生变化,比表面积先减小、后增大。改性后,活性炭纤维表面活性位点有所增加,对应的吸附性能显著增加,30%双氧水改性活性炭纤维对SO₂、NO₂、NO的饱和吸附量分别为100、153、128 mg/g,与改性前相比,分别提高了67%、180%、137%。应用吸附材料的防护包装内部腐蚀气氛浓度在3个月内几乎为0。结论 双氧水改性活性炭纤维具有良好的腐蚀气氛吸附性能,在长贮微环境中具有良好应用前景。     

The supply behaviour of state mining enterprises: A case study of the Jordanian phosphate industry

An important feature of export-oriented production in mineral-rich developing countries for almost three decades after 1960 was the growth of state-owned enterprises. For the phosphate industry, this was reflected in the expansion of companies such as Office Cherifienne des Phosphate (OCP) in Morocco and the Jordan Phosphate Mines Company (JPMC). There was a strategic importance of the industry for these nations and the large capital outlays necessary for phosphate and fertilizer production expansion often required considerable government assistance because of the perceived high risks of private investment in the industry.     

再生气氛对CuO/AC脱硫活性的影响

本文考察了不同气氛再生后ＣｕＯ／ＡＣ脱硫剂的二次脱硫活性,并藉借助ＸＲＤ和ＸＰＳ表征技术以及对再生后脱硫剂残硫的分析,探讨了脱硫剂以不同还原剂在不同温度下再生后二次脱硫活性差异的内在原因,结果表明：脱硫剂经Ｈ２再生后二次脱硫活性与初活性相比出现大幅度下降,Ｈ２气氛中添加Ｈ２Ｏ可提高其二次脱硫活性;经ＮＨ３在３００℃再生后二次脱硫活性与初活性相当,两次再生后仍未观察到活性的明显下降,ＮＨ３再生时脱硫     

模拟油田采出水中H2S的脱除

采出水经处理后通常需作为地层回注水使用,由于油气生产的特殊性,常用的H2S脱除方法在使用中受到限制,探索适合于油气田生产的水处理方法十分必要。文章探讨了通常可用于油田采出水中H2S脱除的各种方法,对比了各类方法的优缺点,提出以NaClO为主要脱硫剂的水处理方法,通过对模拟采出水的室内实验,证明次氯酸法可以快速有效地去除采出水中的H2S,使H2S残留量低于1 mg/L。实验表明:经处理后的水质可以达到SY/T 5329-2012《碎屑岩油藏注水水质指标及分析方法》要求,处理成本较低。     

聚乙烯醇在超临界水氧化中降解

以H2O2为氧化剂用间歇式超临界水氧化装置对聚乙烯醇(PVA)废水进行降解研究。通过正交实验,考察了反应温度、压力、时间及氧化剂过氧倍数对降解效果的影响,并且采用GC/MS对液相降解产物进行表征推测其可能降解途径。结果表明:PVA在SCWO体系中能完全降解,反应温度440℃、压力28 MPa、氧化剂过氧倍数4、反应40 min时,COD去除率为99.03%,出水COD=89.09 mg/L。PVA在SCWO体系中降解为烯烃、烯酮、醇和羧酸类中间产物、最终降解为小分子的饱和直链烷烃类液相产物。     

化学淋洗—H2O2-O3-UV复合催化氧化技术修复硝基甲苯一氯、二氯代物污染土壤工程实例

针对某退役化工企业地块的关注污染物硝基甲苯一氯、二氯代物的历史形成、污染状况和土质特点,在小试技术验证的基础上,采用化学淋洗—H₂O₂-O₃-UV复合催化氧化技术进行受污染土壤异位修复的工程实践。结果表明,该技术能较好地适用于关注污染物的土壤修复工程,修复后指标明显优于目标值,且造价和运行费用较低,具有显著的社会效益、经济效益和环境效益,有一定的推广价值。     

Exposure of the marine deposit feeder Hydrobia ulvae to sediment associated LAS

Linear Alkylbenzene Sulfonates (LAS) effects (mortality, egestion rate, behaviour) on the marine deposit feeder Hydrobia ulvae were assessed in whole-sediment and water-only systems. The results were combined with a bioenergetic-based kinetic model of exposure pathways to account for the observed toxicity. The 10-d LC50 value based on the freely dissolved fraction was 9.3 times lower in spiked sediment (0.152 ± 0.001 (95% CI) mg/L) than in water-only (1.390 ± 0.020 (95% CI) mg/L). Consequently, the actual 10-d LC50 value (208 mg/kg) was overestimated by the Equilibrium Partitioning calculation (1629 mg/kg). This suggests that the sediment associated LAS fraction was bioavailable to the snails. It could also be due to modifications in physiological parameters in absence of sediment, the organism natural substrate.