聚偏氟乙烯本体亲水改性处理油水乳液的研究

为改善PVDF亲水性,本研究利用TMAH对其本体改性产生碳碳双键,将SBMA在BPO引发下接枝到PVDF上,得到PSBMA-g-PVDF油水分离膜.该方法成功将SBMA接枝到PVDF膜上.TMAH含量与接枝率呈正相关关系,通量随接枝率增长而上升,最大为594.9 L/(m^(2)·h),截留率为93.1%,通量恢复率为91.8%,接触角降至29.3°.与PVDF膜相比,PSBMA-g-PVDF膜的分离性能明显提高.

Cracking of Palm Oil over H-AIMCM-41 Catalyst

The objective of this research was to develop a catalyst for efficient cracking of palm oil to produce biogasoline. Mesoporous alumino-silicate, A1MCM-41, was synthesized by hydrothermal treatment to the mixture of sodium silicate, sodium aluminates, TMAOH （tetramethylammonium hydroxide）, and CTMAB （cetyltrimethylammonium bromide）, in Aquadest as a solvent. This process was carried out within 12 h of aging time at 100 ℃ in a teflon-lined stainless steel autoclave. The solid phase was filtered, then washed with distilled water, and dried in an oven at 80 ℃ for 24 h. The surfactant CTMAB was removed by calcination at 540 ℃ for 6 h using heating rate of 2 ℃/min. The as-synthesized and calcined powder was characterized by using FTIR （frontier transform infra red spectroscopy）, XRD （X-ray diffraction）, and TEM （transmission electron microscopy） methods. The product of AIMCM-41 was then converted into H-AIMCM-41 by ion exchanged in 0.5 M of NHaCI solution followed by filtration, drying at 80 ℃ for 24 h, and calcination at 540 ℃. The product of catalyst was used for catalytic conversion of PO （palm oil） to biogasoline in a fixed bed reactor at 200-400 ℃, under atmospheric pressure, and ratio of PO to catalyst was 200. The product of cracking was then distilled at 60 ℃ and analyzed using GC-MS （gas liquid chromatography - mass spectrometry） method. Result of the works shows that the catalyst had 4.49 nm of lattice parameter, and the cracking of PO gave 56.6% conversions with 29.4% selectivity to biogasoline like fraction.

A Novel Silicon Etching Method Using Vapor of Tetramethylammonium Hydroxide Solution

Silicon bulk etching is an important part of micro-electro-mechanical system(MEMS) technology. In this work, a novel etching method is proposed based on the vapor from tetramethylammonium hydroxide(TMAH) solution heated up to boiling point. The monocrystalline silicon wafer is positioned over the solution surface and can be anisotropically etched by the produced vapor. This etching method does not rely on the expensive vacuum equipment used in dry etching. Meanwhile, it presents several advantages like low roughness, high etching rate and high uniformity compared with the conventional wet etching methods. The etching rate and roughness can reach 2.13 μm/min and 1.02 nm, respectively. Furthermore,the diaphragm structure and Al-based pattern on the non-etched side of wafer can maintain intact without any damage during the back-cavity fabrication. Finally, an etching mechanism has been proposed to illustrate the observed experimental phenomenon. It is suggested that there is a water thin film on the etched surface during the solution evaporation. It is in this water layer that the ionization and etching reaction of TMAH proceed, facilitating the desorption of hydrogen bubble and the enhancement of molecular exchange rate. This new etching method is of great significance in the low-cost and high-quality micro-electromechanical system industrial fabrication.

Synthesis and characterization of methacrylate matrix resin bearing o-nitrobenzyl group

The matrix polymer PTBCHNB bearing o-nitrobenzyl group was successfully synthesized by copolymerization of tertiary-butyl methacrylate(TBMA), cyclohexyl methacrylate(CHMA) and o-nitrobenzyl methacrylate(NBMA) via reversible addition fragmentation chain transfer(RAFT) polymerization method. PTBCHNB was characterized by FTIR, 1HNMR, GPC and DSC. After UV irradiation, the o-nitrobenzyl groups of PTBCHNB were photocleaved and the resulting carboxyl groups were highly alkali soluble, and PTBCHNB was converted to PCHIBMA bearing carboxyl groups. So, the matrix polymer could be etched by mild alkali solution with no requirements of photoacid generators and other diverse additives. The photocleavable behaviors of PTBCHNB were determined by FTIR, 1H NMR and TGA analysis. The resist formulated with PTBCHNB and cast in THF solution showed square pattern of 10 μm×10 μm using a mercury-xenon lamp in a contact printing mode and tetramethyl-ammonium hydroxide aqueous solution as a developer.

善用洗消剂防治化学物质溅身的伤害

生产车间或化学实验室的日常作业中发生化学物质溅身后,如何立即进行有效处理,是将灼伤与随后可能出现的并发症降到最低的重要策略。对分别被苯酚、氢氧化四甲基铵、氢氟酸溅伤的4例患者的治疗经过进行回顾,发现:患者使用敌腐特灵或六氟灵处理伤口后,因化学性灼伤引起的刺痛感、灼热感、红肿和胸痛等症状均减轻,且后续也未发生任何并发症。因此,在接触有致死风险的化学物质之后,如能运用适当的洗消剂,尽早进行灼伤伤口的洗消,对保护工人健康至关重要。