甲烷在MnO↓2/SiO↓2催化剂表面吸附的原位FT-IR研究

本文使用付立叶变换红外研究了甲烷在ＭｎＯ２／ＳｉＯ２催化剂表面的吸附，催化剂经高温（７７３Ｋ）抽空处理后，冷却至１７３Ｋ，进２４６６Ｐａ甲烷。在３００８，２９０４和１３０４ｃｍ＾－１吸收峰归属为Ｃ－Ｈ键的对称伸缩振动，这一红外吸收峰的出现说明了甲烷分子的Ｔｄ点群发生畸变，对称性降低。因为红外惰性的２９１７ｃｍ＾－１红外峰显示出红外活性并位移至２９０４ｃｍ＾－１甲烷吸附于ＭｎＯ２／ＳｉＯ２表面后，

甲烷在MnO↓2/SiO↓2催化剂表面吸附的原位FT-IR研究

本文使用付立叶变换红外研究了甲烷在ＭｎＯ２／ＳｉＯ２催化剂表面的吸附，催化剂经高温（７７３Ｋ）抽空处理后，冷却至１７３Ｋ，进２４６６Ｐａ甲烷。在３００８，２９０４和１３０４ｃｍ＾－１吸收峰归属为Ｃ－Ｈ键的对称伸缩振动，这一红外吸收峰的出现说明了甲烷分子的Ｔｄ点群发生畸变，对称性降低。因为红外惰性的２９１７ｃｍ＾－１红外峰显示出红外活性并位移至２９０４ｃｍ＾－１甲烷吸附于ＭｎＯ２／ＳｉＯ２表面后，

甲烷氧化菌Methylomonas sp．GYJ3中甲烷单加氧酶基因与16S rRNA序列分析

甲烷氧化细菌中的关键酶系甲烷单加氧酶是一个含双核铁的多组份氧化酶，常温、常压下能够催化甲烷转化为甲醇。对甲烷氧化细菌Methylomonas sp．GYJ3中溶解性甲烷单加氧酶基因和16S rDNA进行了测序与分析。利用已知相关基因数据库信息，设计了PCR引物和测序引物，获得了满意的测序结果。全长的溶解性甲烷单加氧酶基因为5690bp，部分16S rDNA的序列长度为1280bp。与已发表的甲烷氧化细菌中甲烷单加氧酶进行了比较，结果表明MMOX组份中氨基酸序列的同一性为78％到99％，基因序列的同一性为71％到97％，6个组份中orfY片段的同一性相对较低。MMOX氨基酸序列的多序列联配表明，MMOX序列具有高度保守性，特别是在双核铁中心区域。16S rDNA进化分析显示Methylomonas sp．GYJ3与γ蛋白细菌是相关联的，基于MMOX氨基酸序列的进化分析证明，与Methylomonas sp．GYJ3最近似的菌株是Ⅰ型甲烷氧化细菌Methylomonas sp．KSWⅢ。综合分析表明，菌株GYJ3属于Ⅰ型甲烷氧化细菌Methylomonas sp．属。这个结果为Ⅰ型甲烷氧化细菌也能表达溶解性甲烷单加氧酶提供了新的证据。羟基化酶的理论等电点是6．28，理论分子量为248874．41Da

Influence of buffers on the electrodeposition of nickel from a Watts bath

缓冲剂对镀镍过程作用机理的研究①高灿柱鹿玉理刘汝涛陈方（山东大学环境工程系济南２５０１００）李树本（中国科学院兰州化学物理研究所兰州７３００００）电镀镍是量大面广的镀种，它作为镀铬、贵金属、仿金、枪黑、黑镍的底层，用途非常广泛［１］．在镀镍过程中，...The electrochemical reactions occurring during the deposition of nickel from Watts bath have been examined using the voltammetric technique. The important reactions taking place at the anode and cathode have been identified. The influence of buffers HAc,H_3BO_3 and NH_4Cl on the rate of nickel deposition was marked in the lower concentration (0.01-0.05 mol/L) of buffers. The reason why buffers make the rate of nickel deposition increase were discussed.作者联系地址：山东大学环境工程系,中国科学院兰州化学物理研究所Author's Address: Dep.of Env.Eng.Shandong Univ.Jinan,Shandong 25000Li ShubenLanzhou Inst. of Chem. Phy. Chinese Acad. of Sci.Lanzhou,Gansu,73000

InGaAs/InP PIN photodiodes fabricated by LP-MOCVD

【中文摘要】 采用ＬＰ－ＭＯＣＶＤ制作了ＩｎＧａＡｓ／ＩｎＰ平面型ＰＩＮ光电二极管。器件光敏面直径为７５μｍ，采用Ｚｎ扩散形成ＰＮ结，－６Ｖ偏置下其暗电流低达８～１３ｎＡ；反向击穿电压为６０Ｖ（１μＡ）。在没有增透膜时，对１．３μｍ注入光响应度为０．５６Ａ／Ｗ，光谱响应范围为０．９０～１．７０μｍ。 【英文摘要】 Planar In/InGaAs/InP heterostructure photodiodes are fabricated using LP-MOCVD.The 75 μm diameter device with a PN junction formed by Zn diffusion shows low dark current of 8￣13 nA at bias voltage of -6V.The breakdown voltage is 60 V(1 μA) and the range of spectral response is λ=0. 90￣1.70μm and photodiode response is 0.56 A/W at the 1.3 μm wavelength.福建省自然科学基

InGaAs/InP PIN photodiodes Fabricated by LP-MOCVD

采用lP-MOCVd制作了IngAAS/InP平面型PIn光电二极管。器件光敏面直径为75μM，采用zn扩散形成Pn结，-6V偏置下其暗电流低达8~13nA；反向击穿电压为60V（1μA）。在没有增透膜时，对1.3μM注入光响应度为0.56A/W，光谱响应范围为0.90~1.70μM。Planar In/InGaAs/InP heterostructure photodiodes are Fabricated using LP-MOCVD.The 75 μm diameter device with a PN junction Formed by Zn diFFusion shows low dark current of 8￣13 nA at bias voltage of -6V.The breakdown voltage is 60 V(1 μA) and the range of spectral response is λ=0.90￣1.70μm and photodiode response is 0.56 A/W at the 1.3 μm wavelength.福建省自然科学基

新疆油田准噶尔盆地复杂地质条件深井、超深井钻井技术

该课题针对准噶尔盆地的地质条件，形成了“地层孔隙压力检测预测综合应用”等十多项实用技术及相关软件，包括提高预探井地层孔隙压力、破裂压力和坍塌压力的预测、检测精度；提高地应力分布规律及对井壁稳定影响的机理及对策；钻头合理选型及钻进配套工艺；深井陡构造高效防斜技术；深井复杂情况及事故的预测及处理技术；高温、高压、高密度钻井液性能稳定性技术；提高低压易漏长封固段固井、高温高压气井固井技术；高扭距涡轮节、长寿命轴承组可靠性分析。该项目提高了新疆油田准噶尔盆地复杂地质条件深井、超深井钻井技术水平，促进了准噶尔盆地腹部和南缘山前构造带的勘探步伐，提高了综合经济效益

JUNO Sensitivity on Proton Decay p→νˉK+p\to \bar\nu K^+ Searches

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this paper, the potential on searching for proton decay in $p\to \bar\nu K^+$ mode with JUNO is investigated.The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits to suppress the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar\nu K^+$ is 36.9% with a background level of 0.2 events after 10 years of data taking. The estimated sensitivity based on 200 kton-years exposure is $9.6 \times 10^{33}$ years, competitive with the current best limits on the proton lifetime in this channel