Detailed analysis and simulation verification for reconstruction of plasma optical boundary with spectrometric technique on HL-2M tokamak

The plasma optical boundary reconstruction technique based on Hommen's theory is promising for future tokamaks with high parameters. In this work, we conduct detailed analysis and simulation verification to estimate the ‘logic loophole' of this technique. The finite-width effect and unpredictable errors reduce the technique's reliability, which leads to this loophole. Based on imaging theory, the photos of a virtual camera are simulated by integrating the assumed luminous intensity of plasma. Based on Hommen's theory, the plasma optical boundary is reconstructed from the photos. Comparing the reconstructed boundary with the one assumed, the logic loophole and its two effects are quantitatively estimated. The finite-width effect is related to the equivalent thickness of the luminous layer, which is generally about 2-4 cm but sometimes larger. The level of unpredictable errors is around 0.65 cm. The technique based on Hommen's theory is generally reliable, but finite-width effect and unpredictable errors have to be taken into consideration in some scenarios. The parameters of HL-2M are applied in this work.

Spectrometric study of α-methylene aromatic araminenone and aminoketone

Thirteen α-methylene aromatic araminenone and four α-methylene aromatic aminoketones were prepared by modified Mannich reaction. On the basis of isotopic labeling, a plausible way of cleavage was proposed for the formation of the M^＋- 17 fragment peak in the MS of the α-methylene aromatic araminenone and aminoketones. The characteristic chemical shift of the olefinic protons in ^1H NMR is also discussed.

GAS CHROMATOGRAPHIC-MASS SPECTROMETRIC ANALYSIS OF ANABOLIC STEROIDS IN HUMAN URINE

A new GC/MS method for detection and identification of 19 anabolic steroids in human urine is presented.The procedure involves adsorption and isolation on a macroporous XAD-2 resin,enzymatic hydrolysis,alkaline extraction,derivatization,GC separation and MS detec- tion.Gas chromatographic-mass spectrometric data illustrate artifacts arising from enzymatic hydrolysis of steroid glucuronides and the structural characterization of their metabolites. Using this method,metabolic studies of these steroids in human urine were made after their ingestion by normal and healthy male volunteers.This method was proven to be suitable for large-scale routine analysis of anabolic steroids and was used successfully in passing the doping control test held by the Medical Commission of the International Olympic Committee.

Spectrometric Study of α-Phenylcinnamic Acids

Fourteen substituted α-phenylcinnamic acids were prepared by the classical Perkin condensation. A plausible way of cleavage was involved in the formation of the specific fragment peaks in the MS of the α-phenylcinnamic acids . The characteristic chemical shift of the olefinic proton in HNMR is also discussed

Mass Spectrometric Study of Clusters Produced by Laser Vaporization of Some Phosphates

The clusters generated by direct laser vaporization of KH2PO4 and Cu-3(PO4)(2) samples are studied by a TOF mass spectrometer. It is found that mainly the [K(KPO3)(n)]* cluster series is generated from KH2PO4 sample and it demonstrates obvious magic numbers, which are n=3, 6, 9, 12, 15. Direct laser vaporization of Cu-3(PO4)(2) sample produced [Cu(CuPO3)n]* cluster series as well as other series with the same building block of (CUPO3).

Determination of Fenofibrate and the Degradation Product Using Simultaneous UV-Derivative Spectrometric Method and HPLC

Two new selective, precise, and accurate methods were developed for the determination of fenofibrate in the presence of its basic degradation product. In the first method fenofibrate was determined using an algorithm bivariate calibration derivative method, in which an optimum pair of wavelengths was chosen for the determination of different binary mixtures. In the second method (HPLC), separation was achieved on RESTEK Pinnacle II phenyl column (5 μm, 250 × 4.6 mm) and Pinnacle II phenyl (5 μm, 10 × 4 mm) guard cartridge using a mobile phase consisting of methanol –0.1% phosphoric acid (60:40, v/v) at a flow rate 2 mL●min–1, and the column oven temperature was set at 50°C. The UV detector was time programmed at 302 nm and 289 nm for the internal standard (I.S.) and fenofibrate, respectively. The proposed methods were successfully applied for the determination of fenofibrate and its degradation product in the laboratory-prepared mixture and in pharmaceutical formulation. The assay results obtained using the bivariate method were statistically compared to those of the HPLC method and good agreement was observed.

Chemical Analysis of Magnesia and Magnesia-Alumina Refractory Materials——Flame atomic absorption spectrometric method for determination of calcium oxide content

1 Scope This standard specifics the determination of calcium oxide coutent by flame atomic absorption spectrometric method.

Specific Mass Spectrometric Fragmentations from the Dissociation of Intermediate Ion-Neutral Complexes

It is reported that two kinds of specific mass spectrometric fragmentations are generated from dissociations of the intermediates of both the ion-neutral complex and the proton-bound complex. Collision-induced dissociation, isotopic labelling, and semi-empirical AM1 calculations were used to investigate the formation mechanism of the ion of m/z 139 from ionized tetrahydroimidazole-substituted methylene beta-diketones and the unimolecular fragmentations pathway of 3-phenyl-1-butyn-3-ol upon electron impact.

The“depict”strategy for discovering new compounds in complex matrices:Lycibarbarspermidines as a case

The comprehensive detection and identification of active ingredients in complex matrices is a crucial challenge.Liquid chromatography coupled with high-resolution mass spectrometry(LC-HRMS)is the most prominent analytical platform for the exploration of novel active compounds from complex matrices.However,the LC-HRMS-based analysis workflow suffers from several bottleneck issues,such as trace content of target compounds,limited acquisition for fragment information,and uncertainty in interpreting relevant MS2 spectra.Lycibarbarspermidines are vital antioxidant active ingredients in Lycii Fructus,while the reported structures are merely focused on dicaffeoylspermidines due to their low content.To comprehensively detect the new structures of lycibarbarspermidine derivatives,a“depict”strategy was developed in this study.First,potential new lycibarbarspermidine derivatives were designed according to the biosynthetic pathway,and a comprehensive database was established,which enlarged the coverage of lycibarbarspermidine derivatives.Second,the polarity-oriented sample preparation of potential new compounds increased the concentration of the target compounds.Third,the construction of the molecular network based on the fragmentation pathway of lycibarbarspermidine derivatives broadened the comprehensiveness of identification.Finally,the weak response signals were captured by data-dependent scanning(DDA)followed by parallel reaction monitoring(PRM),and the efficiency of acquiring MS2 fragment ions of target compounds was significantly improved.Based on the integrated strategy above,210 lycibarbarspermidine derivatives were detected and identified from Lycii Fructus,and in particular,170 potential new compounds were structurally characterized.The integrated strategy improved the sensitivity of detection and the coverage of low-response components,and it is expected to be a promising pipeline for discovering new compounds.

Spectrometric Study on the Interaction of Indocyanine Green with Human Serum Albumin

The interaction of indocyanine green（ICG） with human serum albumin（HSA） was investigated via various spectrometric（UV-visible, fluorescence and circular dichroism） techniques. The experimental results indicate that the interaction of ICG with HSA depends on the values of R（R is defined as the molar ratio of HSA to ICG）. The interaction of 1CG with HSA can form two complexes with intrinsic binding constants（Ka） of 2.97×105（R≤2） and 2.63×104（R〉2）, respectively. The fluorescence and induced CD（ICD） spectra of ICG demonstrate that binding the first mole of HSA to ICG can form a chiral ICG-HSA complex with strong fluorescence emission, and the chirality and fluorescence of ICG-HSA complex can be significantly reduced by adding another mole of HSA to 1CG. Furthermore, although both ICG and ICG-HSA complexes followed an energy-dependent endocytosis process to enter living cells, the cellular uptaken dynamic mechanism of ICG was significantly affected by the HSA conjugation.

Determination of Variance of Secondary Metabolites in Lettuces Grown Under Different Light Sources by Flow Injection Mass Spectrometric(FIMS)Fingerprinting and ANOVA-PCA

Lettuce(Lactuca sativa L.)is one of the most consumed vegetables in the world and different management practice can result in considerable variability of the secondary metabolites.Flow injection mass spectrometry(FIMS)combined with analysis of variance-principle component analysis(ANOVA-PCA)was used to study differences in the secondary metabolites originat-ing from different lighting conditions(Sunlight,white light,and florescent light)and lettuce varieties(Romaine and Lollo Rossa).Ultra-high-performance liquid chromatography-high-resolution accurate mass spectrometry was used for putative marker compound identification.Quinic acid,caffeic acid,chlorogenic acid,L-chicoric acid,and quercetin malonyl gluco-side varied significantly for Romaine lettuce grown under different light conditions.The study showed that the combination of FIMS fingerprinting and ANOVA-PCA can be a useful tool for the characterization of the sources of variance in plant materials regarding to genetic,environmental,and management factors.

Mass spectrometric studies of cis- and trans-1a,3-disubstituted-1, 1-dichloro-4-formyl-1a ,2,3,4-tetrahydro-1H-azirino [ 1,2-a] [1,5] benzodiazepines

The mass spectrometric behaviour of four cis- and trans-1a, 3-disuhsdtuted-1,1-dichloro-4-formyl-1a,2,3,4-tetrahydro-1H-azirino[1, 2-a] [1, 5]benzodiazepines has been studied with the aid of mass-analysed ion kinetic energy spectrometry and exact mass measurements under electron impact ionization. All compounds show a tendency to eliminate a chlorine atom from the aziridine ring, and then eliminate a neutral propene or styrene from the diazepine ring to yield azirino[1, 2b][1,3] benzimidazole ions. These azirino[1,2-a][1,5]benzodiazepines can also eliminate HCl, or Cl plus HCl simultaneously to undergo a ring enlargement rearrangement to yield 1,6-benzodiazocine ions, which further lose small molecular fragments, propyne or phenylacetylene, with rearrangement to give quinoxaline ions.

GCMS法测定番茄中的邻苯二甲酸酯类化合物

为了解塑膜袋中的PAEs对番茄的污染程度。以套塑膜袋番茄为试材，采用GC-MS法测定番茄皮和番茄肉中的11种PAEs化合物。结果表明，套塑膜袋番茄皮中检出6种PAEs，浓度在0~2.70 mg/kg范围内；茄肉中含有4种PAEs，浓度在0~0.04 mg/kg之间。套纸膜复合袋番茄皮中检出5种PAEs，含量在0~5.17 mg/kg之间；茄肉中检出2种PAEs，浓度为0~0.07 mg/kg。可见塑膜袋中的PAEs对番茄有一定污染，主要富集于番茄皮部分，番茄肉中PAEs浓度较低。

Geophysical Mapping, Geochemical Evidence and Mineralogy for Nuweibi Rare Metal Albite Granite, Eastern Desert, Egypt

The present study aims to shed light on the rare metals of Nuweibiareaalbite granite in the Eastern Desert through the chemical analyses of the two types of fine-grained albite granite (FAG) and medium-grained albite granite (MAG) in addition to mineralogical studies as well as ground spectrometric survey and aeromagnetic mapping. On the basis of ground spectrometric measurements K, eUand eTh distribution maps were obtained. The concentration of K, U and Th content shows maxima (4.5%, 13 ppm and 27 ppm on average, respectively) in the FAG, and (4.5%, 10 ppm and 35 ppm on average) in the MAG. The eU/eTh ratio significantly increases in FAG with higher magma differentiation than MAG reaching 0.63. This paper uses magnetic geophysical methods to investigate geometry and sense of motion across the Nuweibi area. The interpreted structures from the magnetic maps are characterized by two main intersecting sets of NW-SE and NE-SW trending faults in addition to other three minor faults that trend in N-S, NNW-SSE and ENE-WSW directions. The NW-SE trending faults represent the recent sets in the study area where they are dissected and displaced by the other old faults. The Werner depth map shows the interface depths of the granite and basement rocks that extend to great depths ranging from 10 to 380 m. FAG is extended underneath most of the surrounding schist rocks because of their attributed low magnetic intensity that confirmed also with drilling. Microscope and Microprobe analyses indicated that the most important radioactive minerals include uranothorite, thorite, zircon, and monazite. Columbite group minerals represent the most common Nb-Ta host in Nuweibi-albite granites that contain significant levels of Ta (up to 65.4 wt. % Ta2O5) and Nb (up to 60 wt. % Nb2O5), with Ta/(Ta+Nb) ratio ranging from 0.17 to 0.84. Columbite group minerals are represented mostly by columbite-(Mn) and tantalite-(Mn), with Mn/(Mn+Fe) ratio ranging from 0.42 to 0.89. Ixiolite, wodgnite and tapiolite-(Mn) were found only in the FAG indicating the final stages of the evolution of parental granitic magma. The U-Th and U-K variation diagrams suggested that magmatic processes controlled the distribution of these elements. The Scanning Electron-microprobe analyses reveal variable compositions and extents between the MAG and FAG in the Nb, Ta-Ti, Sn-Fe, Mn triangular plot. It is worthy to be noted that because of the higher Ta/Nb ratio in the tapiolite-Mn and ixiolite of FAG in comparison with the coexisting Mn-columbite in the MAG, levels of HfO2 greater than 15% and even attaining 23%, characterized the hafnium zircon in the Nwueibialbite-enriched facies. There is a close correlation between Hf/(Hf + Zr) and Ta/(Nb + Ta) which seems mainly associated with the FAG.

Mineral Chemistry of Two-Mica Granite Rare Metals: Impact of Geophysics on the Distribution of Uranium Mineralization at El Sela Shear Zone, Egypt

The present work aims at identifying Nb-Ta-, Zr-Hf-, REE-, Th-U-bearing two-mica granite from geological, geophysical cross-sections and mineral chemistry studies from three boreholes at G. El Sela shear zone. Microscopically, the three boreholes are composed mainly of two-mica granite. They are composed of K-feldspar, plagioclase, quartz, biotite and muscovite. Accessories are pyrite, zircon, fluorite, rutile, monazite with Th-U-mineralization identified by scanning electron microscope (SEM) and electron probe-microanalyses (EPMA). Chlorite, muscovite, sericite, kaolinite are secondary minerals. Geochemically, two-mica granite boreholes are A-type granites and peraluminous characteristics. They are enriched in large ion lithophile elements (LILE;Ba, Rb and Sr), high field strength elements (Y, Zr and Nb), and LREE but depleted in HREE with negative Eu anomaly. U-enrichment associated with chloritization, muscovitization, albitization, sericitization, kaolinization and argillization results from convective hydrothermal circulation of fluids through brittle structures along the ENE-WSW main shear zone. The ratios Nb/Ta (7.7 - 17.7) and Zr/Hf (16.9 - 26.4) are relatively enriched in the lighter isovalents Ta and Hf. The accessory minerals observed in the two-mica granites are represented by metallic sulfides (pyrite, arsenopyrite, chalcopyrite, galena and sphalerite), Nb-rutile, Hf-zircon, fluorite, monazite, columbite, betafite, thorite, phosphothorite, uranothorite, brannerite, uraninite, coffinite and pitchblende at G. El Sela shear zone. Uraninite with a low Th content indicates a hydrothermal origin of U-mineralization, Thorite, uranothorite, monazite and zircon is the main uranium bearing minerals of magmatic origin within the enclosing granite. The primary U-mineralization has been observed in two boreholes. In order to illustrate the geophysical signature of El Sela U-mineralization, the radiometric, magnetic, and VLF-EM data as well as radon concentration are included. The magnetic, electrical conductivity and radiometric profiles were produced from detailed ground surveys. The shear zone is characterized by relatively weak levels for both K and eTh, but very high eU anomalies (<3500 ppm), Therefore, the Sela shear zone acts as a good trap for U-mineralization. The Sela Shear zone coincides with positive conductivity anomalies, which are the most prominent features on the respective profiles. The magnetic field over the Sela shear zone is also conspicuous by the sharp contrast which makes with the strong negative signatures of the altered microgranite. The radon distribution map showed the presence of seven high anomalies that are mostly controlled by the structures due to the easy movement of radon through them.

Detection of Optical Stability of chiral 2-Methylbutyric Acid in Gas Phase with Quadrupole-Quistor-Quadrupole Mass Spectrometer

Optical stability of chiral 2-methylbutyric acid in gas phase has been detected with Quadrupole-Quistor-Quadrupole tandem mass spectrometer in combination with deuteration. The results show that these compounds are optically unstable in the process of self chemical ionization.

A Novel Approach for Determining the Orientation of 3-Hydroxyl Group of Some Steroids by CIMS

Trimethylchlorosilane was used as a stereoselective reagent to determine the e or a orientation of 3-hydroxyl group of some steroids by chemical ionization mass spectrometry.

Synthesis of a Novel Imidazole Ionic Liquid Modified Mesoporous Silica SBA15 for Selective Separation and Determination of Inorganic Arsenic in Rice

A novel 1-methylimidazole ionic liquid modified SBA15 mesoporous silica(1-MIIL@SBA15) was synthesized and applied to selective separation of inorganic arsenic(iAs) in rice by dispersive solid phase extraction(DSPE), followed by hydride generation-atomic fluorescence spectrometric(HG-AFS) quantification. The prepared sorbent was characterized by FTIR, FESEM, BET and Zeta potential. Key parameters of adsorption and desorption in DSPE were optimized using standard reference material 1568 b rice flour. Under optimal conditions, the limit of detection was 8.776 ng/kg, relative standard deviation was ≤2.0%, and recoveries of iAs were in the 92.3～94.4% range. This method was successfully applied to the determination of iAs in rice. Under acidic condition, the electrostatic interaction between the positively charged 1-MIIL@SBA15 and anionic iAs played an important role in selective iAs separation, rendering this method suitable for iAs analysis.

TWO NEW COMPOUNDS FROM THE MUSHROOM D. INDUSIATA (VENT EX PERS) FISCH

The chemical constituents in ethyl acetate extract from the mushroom D. Indusiata Fisch were studied. Two new compounds (a new terpenol oleate and a new sesquiterpene) were isolated and identitied by using IR, NMR and MS techniques.

Subsoil Natural Physico-Chemical Reactor:Regularity of Natural Processes of Synthesis of Perfect Diamond Crystals

Studies of inclusions(defects)in minerals have shown that the source of carbon in the natural processes of synthesis of perfect diamond crystals is mantle carbon dioxide,(СО2)Р=6.1МPаandδ13С=(-6.1±0.5)‰.A new mechanism for the synthesis of natural crystals of diamond,pyrope,magnetite,quartz,etc.has been developed.It is shown that under the influence of a powerful pulse of tectonogenic energy in some parts of the lithosphere that there are deep faults-tubes,which take root-migrating melt in the direction of the earth’s crust.During migration in the contact zone—“melt-lithosphere rocks”due to their contact interaction-friction,a high-voltage electric field of complex shape is formed,in which CO2 turns into an energy-excited state,its molecules decompose into individual radicals and atoms.In the melt-electrolyte under the influence of an electric field,ions-cations move in certain directions depending on the configuration of the field,which is due to magma,contact with rocks of the lithosphere and the speed of magma in the gap-tube.As they move,these ions undergo numerous collisions with the molecules present there,in particular,СО2 and its atoms and radicals,temporarily forming unstable compounds that fall into the zone with existing iron compounds,etc.OxygenСО2 poatomically detaches from the molecule and forms FeO·Fe2O3(magnetite),and the most energetically advantageous for chemically active carbon atoms in such an environment is that the melt bonds together form a diamond crystal.The isolated SiO2 molecules chemically form a group of garnets,quartz,and the like.