Electronic structure and infrared spectrum of a W_n C^(0,±) (n = 1-6) cluster

WnC0＇± （n= 1-6） clusters are investigated by using the density functional theory （DFT） at the B3LYP/LANL2DZ level. We find that the neutral, anionic and cationic ground state structures are similar within the same size, and constituted by substituting a C atom for one W atom in the structures of Wn＋1 clusters. The natural bond orbital （NBO） charge analyses indicate that the direction of electron transfer is from the W atom to the 2p orbital of the C atom. In addition, the calculated infrared spectra of the WnC0＇± （n= 2-6） clusters manifest that the vibrational frequencies of neutral, anionic and cationic clusters are similar in a range of 80 cm-1-864 cm-1. The high frequency, strong peak modes are found to be an almost stretched deformation of the carbide atom. Finally, the polarizabilities of WnC0＇± （n= 1-6） clusters are also discussed.

Detection of Chlorpyrifos Residues in Akesu Red Fuji Apple based on Near Infrared Spectrum

[Objective] The paper was to explore a method for detecting chlorpyrifos residues in red Fuji apple. [Method] The original spectral data of apple samples sprayed with different volume fractions of chlorpyrifos were collected using near infrared spectrometer at the band of 4 000-10 000 cm^（-1）. The original spectra were pre-treated by a variety of methods, and partial least squares（PLS） model was established for predictive analysis. [Result] Near infrared spectrum showed sensitivity to apple samples sprayed with different volume fractions of chlorpyrifos, but had low precision on pesticide-free samples. Data of blank control group were further eliminated for modeling prediction. The results showed that the results were the best when pre-treated with first derivative（FD）： R=0.987 9; the square error of prediction（SEP） was 0.173 6; the root-mean-square error of cross-validation（RMSECV） was 0.120 5; and the precision was 0.923 4. [Conclusion] Near infrared spectrum can better predict chlorpyrifos residue, providing a new method for detecting chlorpyrifos residues in Akesu red Fuji apple.

Infrared Spectroscopic and Theoretical Studies on Cobalt(Ⅱ) Complex of Maleinitriledithiolate and 4, 4′-Dimethyl-2, 2′-bipyridine

The complete experimental IR spectra and vibrational analysis of the title complex Co(mnt)(dmbpy) were reported in this paper. The results show that the complex molecule has a planar geometry belonging to point group C 2v and ground electronic state with spin quartet. A new method for analyzing vibrational spectra of complicated molecule is established. The essential of this method is to point out main fixed points and pivotal vibrational units in assignment for each fundamental band. Two new symbols η (heaving along the specified direction) and M (midpoint of a bond or unit) were defined for describing the vibrational modes accurately.

Nanosecond-time-resolved infrared spectroscopic study of fast relaxation kinetics of protein folding by means of laser-induced temperature-jump

Elucidating the initial kinetics of folding pathways is critical to the understanding of the protein folding mechanism. Transient infrared spectroscopy has proved a powerful tool to probe the folding kinetics. Herein we report the construction of a nanosecond laser-induced temperature-jump （T-jump） technique coupled to a nanosecond timeresolved transient mid-infrared （mid-IR） spectrometer system capable of investigating the protein folding kinetics with a temporal resolution of 50 ns after deconvolution of the instrumental response function. The mid-IR source is a liquid N2 cooled CO laser covering a spectral range of 5.0μm （2000 cm^-1）-6.5μm （1540 cm^-1）. The heating pulse was generated by a high pressure H2 Raman shifter at wavelength of 1.9μm. The maximum temperature-jump could reach as high as 26±1℃. The fast folding/unfolding dynamics of cytochrome C was investigated by the constructed system, providing an example.

Identifying Gas-Washing and Water-Washing of Oil Reservoirs by Fluorescence and Infrared Spectra of Single Oil Inclusion

Samples in the two oil fields with reported gas-washing and water-washing were collected for fluid inclusion analysis.Micro-fluorescence and Fourier infrared spectra of single oil inclusions were measured to study the different effects of gas-washing and water-washing on oil compositions.The results show that spectral parameter QF_(535)values of the oils altered by gas-washing were expanded toward decreasing and increasing,respectively.The CH_(2)/CH_(3)distribution range ratio does not expand significantly,but the peak values are averaged.And the distribution of H_(2)O/Alkanes has no change.The QF_(535)values of the oils affected by water-washing increased towards the increase direction,and the distribution ranges of both CH_(2)/CH_(3)and H_(2)O/Alkanes increase significantly.The changes of QF_(535)in light oil reservoirs altered by gas-washing and CH_(2)/CH_(3)in heavy oil reservoirs by water-washing are not obvious.Therefore,two spectral parameter distribution trend charts of light and heavy oil reservoirs are summarized to discriminate the gas-washing and water-washing processes.This study is of great practical significance to utilize fluid inclusion analysis to restructure stages and processes of petroleum accumulation.

Infrared Absorption Spectra of Serpentine Cat's Eye from Sichuan Province of China

Infrared （IR） absorption spectra and X-ray powder diffraction （XRD） patterrns of sexpenfine cat＇s eye from Sichuan Province have been investigated, and infrared absorption bands of the serpentine have been assigned in this paper. The results indicate that the bands near 3 600 - 3 700 cm^-1 belong to the stretching absorption band VOH, the bands in 948 - 1 100 cm^-1 axe assigned to the stretching vibraling band Usvo, and the bands at 600 570 and 440 cm^-1 respectively belong to the bending vibration band VOH, δMg-O and δSi-O. The serpentine cat＇ s eye includes two types： chrysotile and antigorite. Chrysotile has a sharp and intensive band at 3 688 cm^-1 and a weak band at 3 643 cm^-1 , while antigorite has only one intensive band in the region. At vibration band VSi-O, chrysotile and antigorite have a similar feature at 1 071 cm^-1, but the band at 980 cm^-1 in anfigorite has been split into two bands in chrysotile - a strong one at 1 027 cm^-1 and a weak one at 949 cm^-1. In addition, antigorite has a characteristic bending vibrating band δMg-O at 570 cm^-1. Based on the analysis of the feature of crystal structure, their IR differences axe well explained.

Studies on Lattice Vibrational Modes of Na_5Eu(WO_4)_4 Single Crystal by Raman Spectrum

Raman and infrared spectra of host luminescent crystal Na_5Eu(WO_4)_4 in several different geometric con- figurations have been investigated.The symmetrical species of lattice vibrational modes of the crystal have been analysed by means of the site group analysis method of group theory.The experimental vibrational modes have been assigned to A_g,B_g,E_g,A_u and E_u of crystal factor group C_(4h).Because the energies of stretching vibrational modes of(WO_4)^(2-)ion groups are very high(in the range of 755～940 cm^(-1)),multiphonon nonradiative transitions of ~5D_2→~5D_1 and ~5D_1→~5D_0 in Eu^(3+)will occur.So it causes Eu^(3+)ions in Na_5Eu(WO_4)_4 to emit ~5D_0→~5F_j(j=1,2,3,4)emissions mainly at room temperature and the emission light of Na_5Eu( WO_4)_4 has high red colour purity.

Crystal microstructure, infrared absorption, and microwave electromagnetic properties of (La_(1-x)Dy_x)_(2/3)Sr_(1/3)MnO_3

The manganite perovskite polycrystal samples of （La1-xDyx）2/3Sr1/3MnO3 （x = 0, 0.1, 0.2, 0.35, and 0.5） doped with Dy were prepared by solid state reaction in atmosphere to measure their X-ray diffraction （XRD） patterns, scanning electric microscope （SEM） images, infrared absorption spectra, and microwave electromagnetic properties. The displacement of the XRD peaks of the samples was found, and the 2θ increases from 0.05o to 0.5o. The grains of undoped La2/3Sr1/3MnO3 not only have the greatest size, but also the most regular shape. The size of the grains decreases as the Dy doping content increases from 0 to 0.5. The infrared absorption spectra of all samples were measured at room temperature. An absorption peak corresponding to the stretching vibration mode of Mn-O bonds appears within the range of 591-629 cm-1. The absorption peak shifts from a higher frequency to a lower one with the decrease of the average ionic radius of A-site. The frequency de- pendence of microwave-absorbing properties, imaginary components of the complex magnetic permeability μ＂ and dielectric permeability ε＂ for all samples was measured at room temperature from 8 to 13 GHz. The results show that the loss of microwave absorption can be attrib- uted to both the magnetic and electric losses. The increase of Dy content not only enhances the microwave absorption but also causes the displacement of the absorption peaks.

Correlations between trace elements in pyrite and gold mineralization of gold deposits on the North China platform

By studying both the microscopic physical and chemical typomorphic characteristics of typical mineral pyrite samples associated with representative gold deposits on the north-central margin of the North China Platform,this paper seeks to identify macroscopic metallogenic mechanisms of gold deposits and to reveal the formation mechanism of lattice gold in pyrite.Typomorphic characteristics of pyrite reveal that pyrite grain size has a negative correlation with gold content.Cubic pyrite,as the dominant crystal form,contains more gold than pentagonal dodecahedral pyrite.Both pyrite crystal forms and chemical compositions indicate that the replacement style of gold deposit formed in a low saturability,low sulfur fugacity,and at temperatures either much higher or much lower than its best forming temperature;comparatively,that of the quartz vein style of gold deposit occurred under conditions with the best temperature,rich in sulfur,and with high sulfur fugacity.The Au/Ag ratios of the pyrites show that both the replacement and quartz vein styles of deposits are mesothermal and hypothermal,while the Co/Ni ratios of the pyrites indicate that the quartz vein style is of magmatic-hydrothermal origin.The X-ray diffraction intensity of pyrite rich in gold is lower than that of pyrite poor in gold at the quartz vein style.In general,with an increase in gold content in pyrite,the total sum intensityΣI decreases.The pyroelectricity coefficient has a negative correlation trend with the values of(Co+Ni+Se+Te)-As and(Co+Ni+Se+Te)/As.The pyrite pyroelectricity of the replacement style is N-type,indicating that it formed under low sulfur fugacity,while that of the quartz vein style is a mixture of P-N types,indicating that it formed under high sulfur fugacity.On the pyroelectricity-temperature diagram,pyrite of the replacement style is mainly distributed between 200 and 270°C,while that of the quartz vein style varies between 90–118 and274–386°C,demonstrating a multistage forming process.In contrast to previous researchers'conclusions,the authors confirm the existence of lattice gold in pyrites through the use of an electron paramagnetic resonance(EPR)test.Au in the form of Au~+,entering pyrite as an isomorph and producing electron–hole centers,makes the centers produce spin resonance absorption and results in EPR absorption peak II.The intensity of auriferous pyrite absorption peak II has certain direct positive correlations with pyrite gold content.The#I and#III absorption peaks of pyrites possibly result from the existence of Ni^(2+)and/or Cu^(2+).γ1,γ2,andγ3 are the strongest and most typical absorption peaks of the infrared spectra of the pyrites.Generally,with the increase in gold content in the pyrite samples,γ1,γ2,andγ3 tend to shift to higher wavenumbers,and the gold content in the pyrite samples has a positive correlation with their relative absorbance.

Rheological Phase Synthesis and Characterization of Copper Monosalicylate

A new structural copper (II) monosalicylate, Cu(OC6H4C02)·H20, was synthesized by the rheological phase reaction method from salicylic acid and copper oxide in 1∶1 mole ratio. The structure was characterized by powder X-ray diffraction, IR and thermogravimetry. The Cu(OC6 H4 CC2)·H20 belongs to monoclinic system, with cell dimension:a=2.136 28(67),b=0. 657 84(22),c=l. 594 09(50) nm, β=108.434(25) ,V=2.125 28(83) nm3,Z=12, Dcalc=2.041 kg·L?1,D obs=2.003 kg·L?1. The crystal water was lost at 96–250°C. The determined magnetic moment and magnetic susceptibility were 1. 947 B. M. and 6. 546×10?6 (287. 20 K), respectively.

The Use of Aloe vera as Natural Coagulant in Algerian Drinking Water Treatment Plant

The purpose of this work is the study the ability of the plant material Aloe vera to act as natural coagulant using raw water obtained from a drinking water treatment plant(Mila,Algeria).Different solvents such as:NaCl;NaOH and HCl were used as chemical activators to extract the active components from the Aloe vera plant,and different coagulation-flocculation experiments were conducted in a jar test apparatus to evaluate the perfor-mance of the extracted coagulant.Also,the effect of coagulant dose on some water parameters such as turbidity,pH,total alkalinity and organic matter were investigated.The results showed that the use of coagulants obtained by using different solvents increases the coagulation efficiency compared to the coagulant obtained from the raw material,for example the maximum turbidity removal efficiency was 28.23,78.07,83.46 and 85.15%when using powdered Aloe vera(raw material),AV-NaCl(0.5 M),AV-NaOH(0.05 M)and AV-HCl(0.05 M),respectively.The results defined,that the residual turbidity obtained in this work,where the Aloe vera was used(after treat-ment by solvents)produced a turbidity lower than the Algerian standard(5 NTU)with initial turbidity(13 NTU).In this study,the infrared spectrum study and analysis has revealed the presence of different functional groups,which are responsible for the coagulation process.

Damage Effect of Space Proton Irradiation with the Low Energy of 50-200 keV on Methyl Silicone Rubber

The damage effects and mechanisms of proton irradiation with 50-200 keV energy to space-grade methyl silicone rubber was performed using a ground-based simulator for space irradiation environment. The changes in surface morphology, mechanicai properties, cross-linking density, glass temperature, infrared attenuated total reflection spectrum, mass spectrum and pyrolysis gas chromatography-mass spectrum indicated that, under lower energy, the proton irradiation would induce cross-linking effect, resulting in an increase in tensile strengths and hardness of the methyl silicon rubber. However, after the irradiation of protons for more than 150 keV, the irradiation induced degradation, which decreased the tensile strengths and hardness, became a dominant effect. A macromolecular network destruction modei for the silicone rubber radiated vvith the protons was proposed.

Spectroscopic Studies on Co(Ⅱ),Ni(Ⅱ),Zn(Ⅱ) Complexes with 4,4'-Bipyridine

Fourier-transform infrared（FTIR）,Raman and ultraviolet-visible spectra of 4,4＇-bipyridine and its me-tal-organic coordination compounds synthesized from 4,4＇-bipyridine and nitrate of Co（Ⅱ）,Ni（Ⅱ） and Zn（Ⅱ） were measured and analyzed,respectively.The main FTIR and Raman bands were assigned in detail.The relationship between these characteristic bands and the structure of ligands and coordination compounds were discussed.

Comparison of Properties between Phytic Acid and RE-phytic Conversion Coatings of Mg-Li Alloy

The properties among of phytic acid conversion coatings,RE-phytic conversion coatings,rare earth conversion coatings and chromate conversion coatings were compared.The surface micrograph and the corrosion morphology of matrix and various coatings were observed,and the polarization curve,amount of hydrogen evolution and coating binding force were tested.The infrared spectra of phytic acid solution,phytic acid conversion coatings and RE-phytic conversion coatings were compared.The results indicated that the phytic acid coating and RE-phytic acid coating have better corrosion resistance and the RE-phytic acid coating is much better.The infrared spectra indicated that the characteristic peak of phytic acid conversion coatings shift left compared to that of phytic acid.The characteristic peak of RE-phytic conversion coating is similar with that of the phytic acid conversion coating.The di-hydrogen phosphate group of phytic acid reacted with metal matrix or rare earth conversion coating to generate hydrophosphate or phosphate.Phytic acid conversion coating consists of magnesium salt,aluminum salt,zinc salt and ferrous salt.The RE-phytic coating contains cerium salt besides those salts.

Chemical and physical characteristics of quartz from gold deposits in the North China platform: relationship to gold mineralization

This paper seeks to identify macroscopic metallogenic mechanisms of various mineral deposits by studying microscopic typomorphic characteristics of typical minerals associated with the deposits and to reveal the mechanism of lattice gold in detail by studying both physical and chemical characteristics of quartz from representative gold deposits in the North China Platform.As part of their extensive research,the authors examine the relationship between trace elements with wall rock,the ore-forming media,and gold immigration of various types of gold deposits,including their salinity,type,temperature.These are key factors to revealing the mineralization mechanism,and indicators for mineral prospecting,exploration,mining,and metallurgical technology.In order to address the questions posed,the following methods were used:field investigations of geology and sampling of the representative gold deposits,physical study and chemical analysis of quartz including,but not limited to,fluid inclusions as well as their compositions and trace elements in quartz,the unit cell parameters,electron paramagnetic resonance spectrum(EPR),and infrared spectroscopic analysis(ISA).As a result of this study,the authors observe the following key findings:unit cell parameters of quartz vary with their contents of foreign elements including gold,paragenetic stage,wall rock type,and other factors;the higher the forming temperature and the lower the gold content in quartz,the smaller the unit cell parameters,and vice versa.Additionally,the EPR absorption lines resulted from the O–Al defect center.The density of these types of hole centers increases and the EPR signal strengthens when the temperature decreases.Based on the findings,the authors conclude that lattice gold exists in quartz.Gold,in the form of Au^(+)and/or Au^(3+),entering quartz and producing an electron–hole center,namely,the O-Au hole center,makes the center produce spin resonance absorption and results in the EPR absorption peak#I.Both unit cell parameters and EPR of quartz can potentially be used in mineral prospecting,relative ore-forming temperature determination,and grade control during mining.

K2SbB3O8： A Novel Boroantimonate)with Isolated [B3O8]^7- Groups

A new boroantimonate K2SbB3O8 has been synthesized by high-temperature solidstate reactions, and its crystals have been obtained by the flux method. The crystal structure has been determined from single-crystal X-ray diffraction analysis. The compound crystallizes in the monoclinic space group P21/c with a = 5.8890（2）, b = 11.0512（4）, c = 10.8951（4）A, β =103.200（4）°, V = 690.32（4） A^3, Z = 4, F（000） = 672, ρc = 3.467 g/cm^3, Mr = 360.38 and μ = 5.215mm^-1. Its structure feature is a three-dimensional framework composed of SbO6 octahedra and isolated [B3O8]^7- groups with K＋ cations residing in the one-dimensional tunnels along the a-axis.Interestingly, the isolated [B3O8]^7- groups are distinct from the known [B3O8]^7- groups, which always connect to each other. The UV-vis-NIR absorption, thermal stability and infrared spectrum are also discussed in this paper.

A Novel Cuckoo Search Algorithm and Its Application

In this paper, the principle of Cuckoo algorithm is introduced, and the traditional Cuckoo algorithm is improved to establish a mathematical model of multi-objective optimization scheduling. Based on the improved algorithm, the model is optimized to a certain extent. Through analysis, it is proved that the improved algorithm has higher computational accuracy and can effectively improve the global convergence.

Jurassic Amber in Lebanon

Reports of amber predating the Lower Cretaceous are unusual and scarce; they mostly refer to amber pieces of millimetric dimension. In the present study, we report the discovery of 10 new outcrops of Jurassic amber in Lebanon. Some of these had large centimetric-sized pieces of amber. The new localities are described, amber is characterized, and its infrared spectra given. Although the new Jurassic amber yielded to date no more than fungal inclusions, this material is significant and promising. The discovery, of several Jurassic outcrops provides crucial information on the prevailing paleoenvironment of that time.

Hydroxyl groups in nonmetamict chevkinite-(Ce): a crystal chemical discussion

The minerals of chevkinite group were commonly considered to be anhydrous minerals. The infrared absorption spectrum of natural nonmetamict chevkinite-（Ce） from the aegirine-alkali granite, Miannlng, Sichuan Province, China, exhibited two broad peaks in the 3600-2800 cm^-1 region owing to the OH stretching. The corresponding H20 content required for the charge balance in formula was 1.27%. The O-H. … O bond lengths maight cover from 0.2658 to 0.2794 nm by the correlated OH stretching energies. An electrostatic charge balance for chevkinite-（Ce） based on the assigned site-population from chemical data was calculated without the hydrogen contribution. The resulting empirical bond-valence sum on 06, 08, 02, 03, 05, and 04 ranged from 1.73 to 1.95 vu. The partial substitution of O by OH may occur in four atom sites： 06, 02, 04, and 05. The small differences in the bond-valence sums between the supposed donors and acceptors may mean a mixed donor/acceptor role of the involved oxygen atoms. The IR spectral features between 3394 and 3035 cm-1 consisted of various hydrous species at different structural sites and orientations. The OH groups in the chevkinlte-（Ce） appeared to be involved in local charge imbalance in the structure and to be present when the mineral crystallized hydrothermally.

Experimental study of surface crystallization on integrated circuit chips

A surface crystallization phenomenon on bonding pads and wires of integrated circuit chip is reported in this paper. Through a lot of experiments, an unknown failure effect caused by mixed crystalline matter is revealed, whereas non-plasma fluorine contamination cannot cause the failure of bonding pads. By experiments combined with infrared spectroscopy analysis, the surface crystallization effect is studied. The conclusion of the study can provide the guidance for IC fabrication, modelling and analysis.