GC-MS测定环己烷氧化液中有机酸和酯的含量

采用气相色谱-质谱联用法(GC-MS)测定环己烷氧化液中的有机酸和有机酯的含量。在GC-MS分析条件下环己烷氧化液直接进样,通过毛细管柱DB-1701,60 m×0.15 mm×0.25μm分离,由电子轰击源选择离子监测模式下进行检测。结果表明:有机酸和有机酯的标准曲线相关系数大于0.98,相对标准偏差均小于7.0%,回收率为94.9%～98.6%。     

基于电泳沉积工艺的低粘附抗菌涂层的制备

低表面能涂层因其优异的防污自清洁能力而受到广泛关注,但现有涂层存在易被细菌和真菌等微生物破坏而导致防污效果下降的问题,因此构建防污抗菌涂层具有深远的意义。本文基于电泳沉积工艺,将乙烯基硅油改性聚丙烯酸酯和固化剂沉积到导电基底,进一步负载纳米银杀菌剂,经过交联固化后获得了兼具抗细菌粘附与杀菌功能的涂层。采用傅里叶变换红外光谱仪(FT-IR)、核磁共振波谱仪(NMR)和扫描电子显微镜(SEM)等对涂层的结构和形貌进行了系统的表征,结果表明,成功合成了兼具低粘附与杀菌功能涂层。涂层表面具有优异的防油污、细菌及血液粘附的能力,涂层对大肠杆菌和金黄色葡萄球菌的抗细菌粘附效果达到99.9%以上。即使经过强酸、强碱等极端环境以及摩擦3000次后,涂层表面仍具有优异的防液体粘附效果。     

耐高温有机胶黏剂研究进展

对国内外耐高温有机胶黏剂的研究进展进行了综述。对耐高温有机胶黏剂的定义、种类做了简明阐述。对环氧树脂、酚醛树脂、有机硅、聚酰亚胺、聚氨酯、氰酸酯等耐高温胶黏剂的制备、性能和应用进行了较详细的论述。分别讨论了各种耐高温有机胶黏剂基体树脂的结构和性能特点以及提高上述胶黏剂耐高温性能的改性方法。对聚苯并咪唑和聚喹嚼啉胶黏剂进行了简介。最后,对耐高温有机胶黏剂今后的发展趋势进行了展望。     

氨噻肟酸与AE-活性酯合成的研究进展

综述了生产氨噻肟酸的几种方法,并对各种方法的特点、存在的问题进行了分析,提出部分步骤采用超临界CO2作为反应体系。总结了工业上用氨噻肟酸和二硫化二苯并噻唑生产AE-活性酯的方法,提出用氨噻肟酸直接与硫醇基苯并噻唑合成AE-活性酯的方法,并从理论上研究其可行性,阐述了用氨噻肟酸直接与硫醇基苯并噻唑合成AE-活性酯的指导性意义。     

Synthesis and characterization of phosphonate and aromatic-based polynorbornene polymers derived from the ring opening metathesis polymerization method and investigation of their thermal properties

In the present study, phosphonate ester, phosphonic acid, and aromatic (phenyl, naphthalene, anthracene) groups containing polymers were synthesized by the ROMP method to analyze thermal properties of these polymers. Thermal stability of the synthesized polymers is tested by thermal gravimetric analysis under nitrogen, air, and microscale combustion calorimetry analysis. Analysis shows that thermal behavior is directly related to the phosphorus level in the copolymer series. All the polymers are thermally stable under nitrogen and air up to 900 °C. Synergistic charring effect under air was observed between aromatic groups and phosphonic acid functionality in the copolymer series. Anthracene units have a greater potential to form carbonaceous char than the naphthalene and phenyl units. Phosphonate ester and naphthalene units bearing copolymers (P3A) gave 8.13% char yield at 900 °C under air. Phosphonic acid derivatives of this polymer, P3D, gave a highest char residue of 17.15% under the same condition. The introduction of phosphonate and phosphonic acid in each copolymer series is also beneficial in reducing the peak heat release rate (PHRR). Cleavage of the phosphonate ester bearing homopolymer (P4) to phosphonic acid (P4A) causes a sharp decrease in the PHRR ratio from 274 to 28.2 W/g. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47085.     

Effect of manifold and port injection of hydrogen and exhaust gas recirculation (EGR) in dairy scum biodiesel - low energy content gas-fueled CI engine operated on dual fuel mode

In this current work, exhaustive research work is conducted in three phases, in the initial phase, WFO was used for producing WFO treated biomass and in the second phase, influence of PFIP and PFIT has been examined. Further in the successive phase, effect of hydrogen HMI, HPI and EGR on the combustion and emission characteristics of CRDI diesel engine operated on dual-fuel mode using DiSOME and PG combination is evaluated. In the current study, in a CRDI engine, PFIT was employed ranging from 0 to 15°CA bTDC and changed in steps of 5 and PFIP was used from 600 to 1000 bar and varied in successive steps of 200 bar. Further flow rate of hydrogen was kept 8 L/min constant and HMIT was employed in the range from TDC to 15°aTDC and changed in stages of 5. Correspondingly, HID was varied from 30 to 90°CA with 30°CA dwell and EGR was used in the range from 0 to 15% by vol. and varied in steps of 5. Outcome of the work showed that, DiSOME-PG operation with 10°bTDC PFIT, 800 bar PFIP, 10°aTDC of HMI, 60°CAHID and 5% EGR rate showed lower BTE by 5.8% and increased smoke levels by 10.8%, HC by 8.6%, CO by 6.5% and marginally decreased NOx by 6.4% was observed in comparison to the same fuel blend with zero EGR at 80% load. Further, marginally amplifiedID and CD with loweredCP and HRR has been noticed. Study revealed thatH₂addition to low calorific value gas (PG), method of pilot fuel addition and EGR is affected dual fuel engine performance, but provided drastic reductions in smoke and NOx emissions.     

Integrated 3D Open Network of Interconnected Bismuthene Arrays for Energy-Efficient and Electrosynthesis-Assisted Electrocatalytic CO2 Reduction

Electrocatalytic CO₂ reduction reaction (CO₂RR) toward formate production can be operated under mild conditions with high energy conversion efficiency while migrating the greenhouse effect. Herein, an integrated 3D open network of interconnected bismuthene arrays (3D Bi-ene-A/CM) is fabricated via in situ electrochemically topotactic transformation from BiOCOOH nanosheet arrays supported on the copper mesh. The resulted 3D Bi-ene-A/CM consists of 2D atomically thin metallic bismuthene (Bi-ene) in the form of an integrated array superstructure with a 3D interconnected and open network, which harvests the multiple structural advantages of both metallenes and self-supported electrodes for electrocatalysis. Such distinctive superstructure affords the maximized quantity and availability of the active sites with high intrinsic activity and superior charge and mass transfer capability, endowing the catalyst with good CO₂RR performance for stable formate production with high Faradaic efficiency (≈90%) and current density (>300 mA cm^?2). Theoretical calculation verifies the superior intermediate stabilization of the dominant Bi plane during CO₂RR. Moreover, by further coupling anodic methanol oxidation reaction, an exotic electrolytic system enables highly energy-efficient and value-added pair-electrosynthesis for concurrent formate production at both electrodes, achieving substantially improved electrochemical and economic efficiency and revealing the feasibility for practical implementation.     

Formation of ordered nanocrystalline CeO2 structures during thermal decomposition of cerium formate Ce(HCOO)3

In this article, we report the formation of ordered porous nanocrystalline ceria CeO₂ during oxidative thermolysis of cerium formate Ce(HCOO)₃. Ordering of the reaction product occurs due to the presence of similar structural elements in the CeO₂ and Ce(HCOO)₃ crystalline lattices. It was shown that the morphology and the structure of the products of thermal decomposition of Ce(HCOO)₃ are greatly influenced by the composition of the gaseous atmosphere, in which the decomposition takes place. During thermal decomposition of Ce(HCOO)₃ in an atmosphere of argon, no ordering of the synthesized CeO₂ nanocrystals is observed. It was concluded that the presence of oxygen in the gaseous atmosphere is crucial for obtaining ordered nanocrystalline CeO₂ from the Ce(HCOO)₃ precursor.     

Short communication Catalytic synthesis of butyric esters with TiSiW_(12)O_(40)/TiO_2

The catalytic activities of TiSiW12O40/TiO2 in synthesizing ethyl ester, propyl ester, n-butyl ester, and amyl ester were reported. It was demonstrated that TiSiW12O40/TiO2 is an excellent catalyst. Various factors concerned with esterifica-tion were investigated. The optimum conditions were found: the mole ratio of alcohol to acid is 1.3:1, the mass ratio of catalyst to reactants is 1.5%, and the reaction time is 1.0 h. Under the optimum conditions, the yields are 88.0% for ethyl ester, 94.5% for propyl ester, 98.6% for n-butyl ester, 99.1 % for n-amyl ester, and 96.7% for iso-amyl ester, respectively.