HMDS在光刻工艺中的作用及验证方法研究

阐述光刻工序中六甲基二硅氮甲烷(HDMS)工序在改善光刻胶和硅片的黏合性能方面的工作原理及效果。通过关键参数试验验证,及对接触角的测量,确定理想的HMDS工艺参数。对光刻工序中的倒胶缺陷案例进行分析,通过调整HMDS工作特效的环境因素及控制方法,在改善光刻产品质量上的作用,给出了集成电路产业半导体芯片生产中光刻工序中出现的倒胶案例分析。

顶空气相色谱法测定头孢唑啉钠中残留溶媒

目的:建立一种气相色谱法同时测定原料药头孢唑林钠中有机溶剂丙酮,二氯甲烷、乙醇残留量的方法。方法:采用双内标顶空自动进样,在中极性弹性毛细管柱上进行分离,效果良好。结果:平均回收率:丙酮100．2％-101．5％;二氯甲烷95．0％-103．1％;乙醇97．8％-101．5％;变异系数:丙酮1．9％;二氯甲烷2．3％;乙醇2．1％。结论:方法重现性好,定量准确,便于操作。

Nitrous Oxide and Methane Emissions as Affected by Water,Soil and Nitrogen

Specific management of water regimes, soil and N in China might play an important role in regulating N2O and CH4 emissions in rice fields. Nitrous oxide and methane emissions from alternate non-flooded/flooded paddies were monitored simultaneously during a 516-day incubation with lysimeter experiments. Two N sources (15N-(NH4)2SO4 and 15N-labeled milk vetch) were applied to two contrasting paddies: one derived from Xiashu loess (Loess) and one from Quaternary red clay (Clay). Both N2O and CH4 emissions were significantly higher in soil Clay than in soil Loess during the flooded period. For both soil, N2O emissions peaked at the transition periods shortly after the beginning of the flooded and non-flooded seasons. Soil type affected N2O emission patterns. In soil Clay, the emission peak during the transition period from non-flooded to flooded conditions was much higher than the peak during the transition period from flooded to non-flooded conditions. In soil Loess, the emission peak during the transition period from flooded to non-flooded conditions was obviously higher than the peak during the transition period from non-flooded to flooded conditions except for milk vetch treatment. Soil type also had a significant effect on CH4 emissions during the flooded season, over which the weighted average flux was 111 mg C m-2 h-1 and 2.2 mg C m-2 h-1 from Clay and Loess, respectively. Results indicated that it was the transition in the water regime that dominated N2O emissions while it was the soil type that dominated CH4 emissions during the flooded season. Anaerobic oxidation of methane possibly existed in soil Loess during the flooded season.

Advances in Greenhouse Gases Emission in Farmland Soils

[Objective] The aim was to overview the emission of greenhouse gases in farmland. [Method] Based on domestic and foreign references, production mechanism, discharging characters and major influential factors of CO2, CH4 and N2O in soils of farmland were overviewed. [Result] Production and discharge of CO2, CH. and N2O played an important role in circulation of carbon and nitrogen in terrestrial ecosystem and constituted a key method for carbon and nitrogen output. It is significant to conduct research on reduction of greenhouse gas and increase of absorption. [Conclusion] The research is beneficial for exploration on discharge rule and influential factors of greenhouse gases, providing theoretical references for reduction of greenhouse gases and study on climate change.

Chiral Bronsted acid-catalyzed conjugate addition of indoles to azadienes:Enantioselective synthesis of hetero-triarylmethanes

An efficient chiral Br?nsted acid-catalyzed conjugate addition of indoles to azadienes has been successfully developed,which enables a facile approach to optically active hetero-triarylmethanes with excellent enantioselectivities and broad substrate scope.This chiral Br?nsted acid catalytic system provides a new opportunity for the development of asymmetric reactions of azadienes.

Synthesis and Crystal Structure of a New Cu^II Complex of N,N'-Bis(quinolin-2-ylmethyl)-1, 4-diazacycloheptane

A new CuII complex with a diazamesocyclic ligand based on 1,4-diazacycloheptane (DACH) and functionalized with two additional quinoline donor groups, namely N,N-bis(quinolin-8- ylmethyl)-1,4-diazacycloheptane L, has been synthesized and characterized. X-ray diffraction analysis at room temperature indicates that the title complex [CuLCl](ClO4) 1 (C25H26Cl2N4O4Cu, Mr = 580.94) crystallizes in triclinic, space group P1 with a = 9.589(3), b = 10.857(4), c = 12.724(5) ? a = 98.168(7), b = 106.945(7), g = 101.248(7), V = 1214.6(8) 3, Z = 2, Dc = 1.588 g/cm3, F(000) = 598 and m(MoKa) = 1.161 mm-1. The final R = 0.0479 and wR = 0.0985 with 4267 independent reflections. In the mononuclear CuII complex, the CuII center is pentacoordinated to four nitrogen donors of the ligand and one axial chloride anion, taking a coordination sphere in the midst of the ideal square- pyramid and trigonal bipyramid.

Nitrous Oxide and Methane Fluxes During the Maize Season Under Optimized Management in Intensive Farming Systems of the North China Plain

Addressing concerns about mitigating greenhouse gas （GHG） emissions while maintaining high grain yield requires improved management practices that achieve sustainable intensification of cereal production systems. In the North China Plain, a field experiment was conducted to measure nitrous oxide （N2O） and methane （CH4） fluxes during the maize （Zea mays L.） season under various agricultural management regimes including conventional treatment （CONT） with high N fertilizer application at a rate of 300 kg N ha-1 and overuse of groundwater by flood irrigation, optimal fertilization 1 treatment （OPTIT）, optimal fertilization 2 treatment （OPT2T）, and controlled-release urea treatment （CRUT） with reduced N fertilizer application and irrigation, and a control （CK） with no N fertilizer. In contrast to CONT, balanced N fertilization treatments （OPT1T, OPT2T, and CRUT） and CK demonstrated a significant drop in cumulative N20 emission （1.70 v.s. 0.43-1.07 kg N ha-l）, indicating that balanced N fertilization substantially reduced N20 emission. The vMues of the N20 emission factor were 0.42%, 0.29%, 0.32%, and 0.27% for CONT, OPTIT, OPT2T, and CRUT, respectively. Global warming potentials, which were predominantly determined by N20 emission, were estimated to be 188 kg CO2-eq ha-1 for CK and 419-765 kg CO2-eq ha-1 for the N fertilization treatments. Global warming potential intensity calculated by considering maize yield was significantly lower for OPT1T, OPT2T, CRUT, and CK than for CONT. Therefore, OPTIT, OPT2T, and CRUT were recommended as promising management practices for sustaining maize yield and reducing GHG emissions in the North China Plain.