Biodegradation of acrylamide by acrylamidase from Stenotrophomonas acidaminiphila MSU12 and analysis of degradation products by MALDI-TOF and HPLC

The present study examines an improved detoxification and rapid biological degradation of toxic pollutant acrylamide using a bacterium. The acrylamide degrading bacterium was isolated from the soil followed by its screening to know the acrylamide degrading capability. The minimal medium containing acrylamide (30 mM) served as a sole source of carbon and nitrogen for their active growth. The optimization of three different factors was analyzed by using Response Surface Methodology (RSM). The bacteria actively degraded the acrylamide at a temperature of 32 degrees C, with a maximum growth at 30 mM substrate (acrylamide) concentration at a pH of 7.2. The acrylamidase activity and degradation of acrylamide was determined by High Performance Liquid Chromatography (HPLC) and Matrix Assisted Laser Desorption and Ionization Time of Flight mass spectrometer (MALDI-TOF). Based on 168 rRNA analysis the selected strain was identified as Gram negative bacilli Stenotrophomonas acidaminiphila MSU12. The acrylamidase was isolated from bacterial extract and was purified by HPLC, whose mass spectrum showed a molecular mass of 38 kDa. (C) 2014 Elsevier Ltd. All rights reserved.

A matrix model for QCD

Gribov's observation that global gauge fixing is impossible has led to suggestions that there may be a deep connection between gauge fixing and confinement. We find an unexpected relation between the topological nontriviality of the gauge bundle and colored states in SU(N) Yang-Mills theory, and show that such states are necessarily impure. We approximate QCD by a rectangular matrix model that captures the essential topological features of the gauge bundle, and demonstrate the impure nature of colored states explicitly. Our matrix model also allows the inclusion of the QCD theta-term, as well as to perform explicit computations of low-lying glueball masses. This mass spectrum is gapped. Since an impure state cannot evolve to a pure one by a unitary transformation, our result shows that the solution to the confinement problem in pure QCD is fundamentally quantum information-theoretic.

Photoproduction of charged pion pairs from hydrogen at energies up to 1500 MeV

Charged pion pair photoproduction has been investigated up to a gamma energy of 1500 MeV, using the Caltech 12-inch heavy liquid bubble chamber with a small diameter, high intensity photon beam passing through a central beam tube gaseous hydrogen target surrounded by the sensitive Freon. Scanning, analysis, and data reduction techniques have been developed to deal with the problems of two-vie stereo, hidden event origins, absence of magnetic field, and the range-energy and multiple scattering relationships that occur in the heavy materials. Roughly 5700 pictures have been scanned and analyzed, yielding 754 acceptable events. Cross section and parameter distributions are generally consistent with the results of previous experiments. A statistically insignificant “bump” was observed in the dipion mass spectrum in the region of 500 MeV, the disputed σ meson mass. This region was investigated as carefully as the limited statistics would allow; dipion angular distributions are consistent with isotropy, and there is indication that some of the events in this region might come from decay of an intermediate N*₁₁ (1425) into a proton and dipion.

Photographic materials on pp. 18, 20, 22, and 24 are essential and will not reproduce clearly on Xerox copies. Photographic copies should be ordered.

Relativistic quark models and the current algebra

In this thesis we are concerned with finding representations of the algebra of SU(3) vector and axial-vector charge densities at infinite momentum (the "current algebra") to describe the mesons, idealizing the real continua of multiparticle states as a series of discrete resonances of zero width. Such representations would describe the masses and quantum numbers of the mesons, the shapes of their Regge trajectories, their electromagnetic and weak form factors, and (approximately, through the PCAC hypothesis) pion emission or absorption amplitudes.

We assume that the mesons have internal degrees of freedom equivalent to being made of two quarks (one an antiquark) and look for models in which the mass is SU(3)-independent and the current is a sum of contributions from the individual quarks. Requiring that the current algebra, as well as conditions of relativistic invariance, be satisfied turns out to be very restrictive, and, in fact, no model has been found which satisfies all requirements and gives a reasonable mass spectrum. We show that using more general mass and current operators but keeping the same internal degrees of freedom will not make the problem any more solvable. In particular, in order for any two-quark solution to exist it must be possible to solve the "factorized SU(2) problem," in which the currents are isospin currents and are carried by only one of the component quarks (as in the K meson and its excited states).

In the free-quark model the currents at infinite momentum are found using a manifestly covariant formalism and are shown to satisfy the current algebra, but the mass spectrum is unrealistic. We then consider a pair of quarks bound by a potential, finding the current as a power series in 1/m where m is the quark mass. Here it is found impossible to satisfy the algebra and relativistic invariance with the type of potential tried, because the current contributions from the two quarks do not commute with each other to order 1/m³. However, it may be possible to solve the factorized SU(2) problem with this model.

The factorized problem can be solved exactly in the case where all mesons have the same mass, using a covariant formulation in terms of an internal Lorentz group. For a more realistic, nondegenerate mass there is difficulty in covariantly solving even the factorized problem; one model is described which almost works but appears to require particles of spacelike 4-momentum, which seem unphysical.

Although the search for a completely satisfactory model has been unsuccessful, the techniques used here might eventually reveal a working model. There is also a possibility of satisfying a weaker form of the current algebra with existing models.

Influence of negative ion element impurities on laser induced damage threshold of HfO2 thin film

Negative ion element impurities breakdown model in HfO2 thin film was reported in this paper. The content of negative ion elements were detected by glow discharge mass spectrum analysis (GDMS); HfO2 thin films were deposited by the electron-beam evaporation method. The weak absorption and laser induced damage threshold (LIDT) of HfO2 thin films were measured to testify the negative ion element impurity breakdown model. It was found that the LIDT would decrease and the absorption would increase with increasing the content of negative ion element. These results indicated that negative ion elements were harmful impurities and would speed up the damage of thin film. (c) 2006 Elsevier B.V. All rights reserved.

HfO2的纯度对紫外多层膜反射率的影响

用辉光放电质谱法和二次离子质谱仪测定了两种HfO2材料及它们相应的单层膜中的杂质含量，结果发现，无论是在体材料中还是在用电子束蒸发技术沉积的材料单层薄膜中，ZrO2都是这两种HfO2材料中最主要的杂质。而且，这两种HfO2材料中Zr含量的差别远远大于Ti、Fe含量的差别，这说明Zr含量的差别正是引起两种HfO2膜层光学性能差别的原因。用这两种不同纯度的HfO2材料与同一纯度的SiO2材料组合，沉积形成266nm的紫外反射镜，实验结果表明这两种反射镜的反射率分别在99.85% 和 99.15%左右。这个结果与依据单层膜得出的光学常数所设计的结果符合的很好。

Influence of ZrO2 in HfO2 on reflectance of HfO2/SiO2 multilayer at 248 nm prepared by electron-beam evaporation

Influence of ZrO2 in HfO2 on the reflectance of HfO2/SiO2 multilayer at 248 nm was investigated. Two kinds of HfO2 with different ZrO2 content were chosen as high refractive index material and the same kind of SiO2 as low refractive index material to prepare the mirrors by electron-beam evaporation. The impurities in two kinds of HfO2 starting coating materials and in their corresponding single layer thin films were determined through glow discharge mass spectrum (GDMS) technology and secondary ion mass spectrometry (SIMS) equipment, respectively. It showed that between the two kinds of HfO2, either the bulk materials or their corresponding films, the difference of ZrO2 was much larger than that of the other impurities such as Ti and Fe. It is the Zr element that affects the property of thin films. Both in theoretical and in experimental, the mirror prepared with the HfO2 starting material containing more Zr content has a lower reflectance. Because the extinction coefficient of zirconia is relatively high in UV region, it can be treated as one kind of absorbing defects to influence the optical property of the mirrors. (C) 2008 Elsevier B.V. All rights reserved.

Compositional analysis of thin film amorphous semiconductors and insulators using LIMA

LIMA (Laser-induced Ion Mass Analysis) is a new technique capable of compositional analysis of thin films and surface regions. Under UHV conditions a focused laser beam evaporates and ionizes a microvolume of specimen material from which a mass spectrum is obtained. LIMA has been used to examine a range of thin film materials with applications in electronic devices. The neutral photon probe avoids charging problems, and low conductivity materials are examined without prior metallization. Analyses of insulating silicon oxides, nitrides, and oxynitrides confirm estimates of composition from infrared measurements. However, the hydrogen content of hydrogenated amorphous silicon (a-Si : H) found by LIMA shows no correlation with values given by infrared absorption analysis. Explanations are proposed and discussed. © 1985.

A serine proteinase inhibitor from frog eggs with bacteriostatic activity

By Sephadex G-50 gel filtration, Resource Q anionic exchange and C4 reversed phase liquid high performance liquid chromatography, a proteinase inhibitor protein (Ranaserpin) was identified and purified from the eggs of the odour frog, Rana grahami. The protein displayed a single band adjacent to the molecular weight marker of 14.4 kDa analyzed by SDS-PAGE. The inhibitor protein homogeneity and its molecular weight were confirmed again by MALDI-TOF mass spectrometry analysis. The MALDI-TOF mass spectrum analysis gave this inhibitor protein an m/z of 14422.26 that was matched well with the result from SDS-PAGE. This protein is a serine proteinase inhibitor targeting multiple proteinases including trypsin, elastase, and subtilisin. Ranaserpin inhibited the proteolytic activities of trypsin, elastase, and subtilisin. It has an inhibitory constant (K-i) of 6.2 x 10(-8) M, 2.7 x 10(-7) M and 2.2 x 10(-8) M for trypsin, elastase, and subtilisin, respectively. This serine proteinase inhibitor exhibited bacteriostatic effect on Gram-positive bacteria Bacillus subtilis (ATCC 6633). It was suggested that ranaserpin might act as a defensive role in resistance to invasion of pests or pathogens. This is the first report of serine proteinase inhibitor and its direct defensive role from amphibian eggs. (C) 2007 Elsevier Inc. All rights reserved.

Extraction and structure elucidation of natural compounds of some gorgonians of the Persian Gulf and also physiological and pharmacological effects of gorgonian extract on some selected organisms

In the present research, investigations were carried out for structure elucidation of natural compounds and also for studing biological and teratogenical effects of two Genus of soft corals named as " Echinogorgia cf. indica" and "Sinularia erecta" in Persian Gulf. First, 350 gr Echinogorgia was extracted by Acetone, then, the extract was separated by ether from aqueos phase to give 4.5 gr oil. The oil eluted with Petrol - ether Et2 o (9:1) which was recovered Linderazulene and it's derivative as purple Cristals (350 mg/ca 0.1 %). In order to determine molecular structure, the Samples were used for spectroscopic method as: H1- NMR , C13- NMR and 2D NMR. Also, for extraction and structure elucidation of natural compounds, the soft coral " sinularia erecta " were used 1187/37 gr and extracted by Aceton. The extract was concentrated and resulting aqueous suspension and extracted by using ether to give 8.41 gr oil. The oil , was Chromatographed on a column of silica gel and some different fractions were gathered. Initial fraction (1-11) which were nonpolar compounds were seprated by GC/MS. Mass spectrum were prepared and much compounds were recognized.

Determination of microcystin-LR and its metabolites in snail (Bellamya aeruginosa), shrimp (Macrobrachium nipponensis) and silver carp (Hypophthalmichthys molitrix) from Lake Taihu, China

This paper describes seasonal changes of microcystin-LR (MC-LR) and its glutathione (MC-LR-GSH) and cysteine conjugates (MC-LR-Cys) in three aquatic animals - snail (Bellamya aeruginosa), shrimp (fMacrobrachium nipponensis) and silver carp (Hypophthalmichthys molitrix) collected from Lake Taihu, China. MC-LR, MC-LR-GSH, and MC-LR-Cys were determined by liquid chromatography electrospray ionization mass spectrum (LC-ESI-MS). The mean MC-LR concentrations in the hepatopancreas of snail and shrimp and liver of silver carp were 6.61, 0.24, and 0.027 mu g g(-1) dry weight (DW), respectively: while the average MC-LR-Cys concentrations were 0.50, 0.97, and 5.72 mu g g(-1) DW, respectively. MC-LR-GSH was usually not detectable in these samples. The above results suggest that: (1) in aquatic animals, especially fish, the main excretion form of MC-LR could be MC-LR-Cys, but not MC-LR-GSH, whereas MC-LR-Cys might play an important role in detoxication of MC-LR and (2) that efficiency of MC-LR-Cys formation differs among species. The main detoxication pathway of MC-LR in aquatic animals is suggested as follows: when MC-LR enters into liver/hepatopancreas, it firstly conjugates with polypeptide or protein (including GSH, PP-1 and 2A) containing Cys residues, perhaps also some free cysteine; subsequently, MC-LR-Cys is degraded from these polypeptide or protein; and finally is excreted from animals by the compound of MC-LR-Cys. (C) 2009 Elsevier Ltd. All rights reserved.

Bioaccumulation of the hepatotoxic microcystins in various organs of a freshwater snail from a subtropical Chinese lake, Taihu lake, with dense toxic microcystis blooms

In this paper, we describe the seasonal dynamics of three common microcystins (MCs MC-RR, MC-YR, and MC-LR) in the whole body, hepatopancreas, intestine, gonad, foot, remaining tissue, and offspring of a freshwater snail, Bellamya aeruginosa, from Gonghu Bay of Lake Taihu, China, where dense toxic Microcystis blooms occur in the warm seasons. Microcystins were determined by liquid chromatography electrospray ionization mass spectrum. Microcystin (MC-RR + MC-YR + MC-LR) content of the offspring and gonad showed high positive correlation, indicating that microcystins could transfer from adult females to their young with physiological connection. This study is the first to report the presence of microcystins in the offspring of the adult snail. The majority of the toxins were present in the intestine (53.6%) and hepatopancreas (29.9%), whereas other tissues contained only 16.5%. If intestines are excluded, up to 64.3% of the toxin burden was allocated in the hepatopancreas. The microcystin content in the intestine, hepatopancreas, and gonad were correlated with the biomass of Microcystis and intracellular and extracellular toxins. Of the analyzed foot samples, 18.2% were above the tolerable daily microcystin intake recommended by the World Health Organization (WHO) for human consumption. This result indicates that public health warnings regarding human ingestion of snails from Taihu Lake are warranted. In addition, further studies are needed to evaluate the occurrence by Microcystis in relation to spatial and temporal changes in water quality.

Study on pollution for the photoelectronic material InP

The mass spectrum analysis of crystal face (100) and (111) and the photoluminescence analysis of crystal face (100) in the photoelectronic material InP were given. The Hall coefficient, charge carrier concentration and Hall mobility were determined. Experimental results indicate that the pollution of silicon is predominant.

西藏产雪莲花的化学成分研究

本学位论文报道了作为传统藏药材广泛使用的西藏产雪莲花化学成分的研究。论文由五章组成，第一章是三种西藏产雪莲花的化学成分的系统分离纯化和结构鉴定；第二章为西藏产雪莲花化学成分的液-质及串联质谱联用分析；第三章提出了以HPLC和TLC为检测方法的雪莲花药材质量标准草案；第四章给出了对西藏产雪莲花挥发油化学成分的气-质联用分析结果；第五章概述了雪莲花的化学成分及药理研究进展。 第一章包括三个部分。第一部分报道了绵头雪莲花(Saussurea laniceps Hand.-Mazz.)全草乙醇提取物化学成分的分离鉴定。采用正相硅胶柱层析及凝胶柱层析等分离方法，从西藏产绵头雪莲花的乙醇提取物中共分离鉴定出15个化合物。其中11个化合物为首次从该植物中分离得到，当中2个化合物系在凤毛菊属植物中首次发现。第二部分报道了水母雪莲花(Saussurea medusa Maxim.)全草乙醇提取物的化学成分。采用正、反相硅胶柱层析及凝胶柱层析等分离方法，共分离鉴定出15个化合物，其中1个为新化合物，另有4个化合物为首次从该植物中分离得到。新化合物结构通过质谱和一维及二维核磁共振等波谱解析方法及碱水解反应确定为巴豆酰基-高车前苷(M-7)。第三部分报道了三指雪莲花 (Saussurea tridactyla Sch.-Bip. ex Hook. f.)全草乙醇提取物的化学成分。采用正相硅胶柱层析及凝胶柱层析等分离方法，共分离鉴定出7个化合物，其中1个化合物为首次从该植物中分离得到。 第二章也包括三个部分。首先是采用液-质联用(HPLC-DAD-ESI-MSn)分析方法，对7个西藏不同产地的三指雪莲花化学成分进行了分析，通过与标准品的 UV和MS数据比较，共鉴定出14个峰，并对其中8个共有成分进行了定量测定。其次是关于八种西藏产雪莲花化学成分的液-质联用(HPLC-DAD-ESI-MSn)分析，通过与标准品的UV和MS数据比较，共鉴定出15个峰，并对其中8个共有成分进行了定量检测。最后通过对八种西藏产雪莲花主要化学成分的多级串联质谱(ESI-MSn)分析，快速、灵敏地鉴定出10个黄酮和3个香豆素化学成分。 第三章同样包括三个部分。首先是以绵头雪莲花中主要香豆素成分东莨菪素和伞形花内酯为对照品，通过TLC定性检测和HPLC含量测定，草拟出较严谨的药材质量标准。其次是将绵头雪莲花、三指雪莲花和雪兔子作为一个药材看待，草拟了以东莨菪素和伞形花内酯的TLC检测为指标的药材质量标准。最后是针对水母雪莲花，以主要黄酮成分芹菜素-7-O-b-D-葡萄糖苷为对照品作TLC检测，并草拟出该药材的质量标准草案。 第四章报道了西藏产雪莲花挥发油的化学成分分析。采用传统水蒸气蒸馏法分别从八种雪莲花全草中提取挥发油，利用气相色谱-质谱联用技术分别从水母雪莲花、绵头雪莲花、槲叶雪莲花、云状雪兔子、拉萨雪兔子、小果雪兔子、雪兔子和三指雪莲花中分别鉴定出83、83、56、34、21、20、24和20个化学成分，分别占其挥发油总量的70.7%、76.0%、82.2%、55.4%、49.7%、70.4 %、76.2%和 76.7%。 第五章为综述，总结和概括了雪莲花的化学和药理研究进展。 The dissertation reports the investigation of the chemical constituents of the genus Saussurea. Quite a lot of species in this genus are traditional Tibetan medicinal plants, and hence have been widely used in traditional Tibetan medicine. This dissertation consisted of five chapters. The first chapter is on the chemical constituents of three Saussurea plants. The second section is about the analysis of chemical constituents of Saussurea plants using HPLC-MS and ESI-MS/MS. In the third chapter, we proposed quality-control standards for the Genus Saussurea based on TLC (thin layer chromatography) and HPLC. The fourth chapter is about chemical compositions of the essential oil from the whole plant of Saussurea plants. The last chapter reviews the research progress of the Genus Saussurea. The first chapter consists of three parts. The first part is about chemical constituents of ethanol extracts from whole plant of Saussurea laniceps Hand.-Mazz. Fifteen compounds were isolated by column chromatography on normal phase silica gel and Sephadex LH-20. Among them, eleven compounds were isolated from this plant for the first time, and two compounds were isolated from Genus Saussurea for the first time. The second part is about chemical constituents of ethanol extracts from whole plant of Saussurea medusa Maxim. Fifteen compounds were isolated by column chromatography on normal phase, reversed phase silica gel and Sephadex LH-20. Five of them were isolated from this plant for the first time, and there is one new flavonoid glucoside which was identified as 6″-O-crotonoyl-homoplantaginin (M-7) based on the evidence of one- and two-dimensional nuclear magnetic resonance, mass spectrometry analysis, and alkaline hydrolysis reaction. The last part is about chemical constituents of ethanol extracts from whole plant of Saussurea tridactyla Sch.-Bip. ex Hook. f.. Seven compounds were isolated by column chromatography on normal phase silica gel and Sephadex LH-20. There is one compound which was isolated from this plant for the first time. The second chapter consists of three parts. In the first part, we analyzed the chemical constituents of S. tridactyla collected from seven different places in Tibet using HPLC-DAD-ESI-MSn. Fourteen peaks in the HPLC were identified by comparison of UV and MS spectra with those of authentic compounds, among which eight common peaks were quantified. In the second part, we analyzed the chemical constituents of eight Saussurea species using HPLC-DAD-ESI-MSn method. Fifteen peaks in the HPLC were identified by comparison of UV and MS spectra with those of authentic compounds and eight main peaks of them were quantified. In the last part, we analyzed the chemical compounds of the above eight Saussurea plants directly by ESI-MS/MS. Thirteen major compounds, including 10 flavonoids and 3 coumarins were easily rapidly identified. The third chapter consists of three parts. In the first part, we proposed a comparative high quality-control standard for S. laniceps, based on quality detection by TLC and quantity analysis by HPLC using two major compounds (umbelliferone and scopoletin) as standard compounds. In the second part, in viewing S. laniceps, S. tridactyla and S. gossypiphora as the members of one family of medicinal herbs, we suggested a quality-control standard based on the TLC detection of the two major compounds (umbelliferone and scopoletin). In the last part, we proposed a quality-control standard for S. medusa based on the TLC detection of its major component (apigenin 7-O-glucoside). The four chapter analyzed the chemical constituents of essential oil of eight Saussurea species. The essential oils were extracted from the whole plants of these samples with water stream distillation. By GC-MS analysis, we identified eighty-three compounds from S. medusa, eighty-three from S. laniceps, fifty-six from S. quercifolia, thirty-four from S. aster, twenty-one from S. kingii, twenty from S. simpsoniana, twenty-four from S. gossypiphora, and twenty from S. tridactyla respetively, which accounted for 70.7%, 76.0%, 82.2%, 55.4%, 49.7%, 70.4 %, 76.2% and 76.7% of the total essential oil, respectively. The last chapter reviews the research progress of the Genus Saussurea.