Analysis of Chemical Research Progress on Graphene

Graphene materials have excellent optical and electrical properties,and in recent years,significant achievements have been made in the chemical improvement and preparation of graphene.This article analyzes the progress in the chemical preparation,chemical modification,surface chemistry,and catalysis of graphene,in order to provide reference for relevant personnel.

Physico-Chemical Analysis of Soils Used for Pineapple Cultivation in the Sub-Prefectures of Maferinyah and Friguiagbé (Prefectures of Forécariah and Kindia) Republic of Guinea

Over the years, pineapple production in the Republic of Guinea has become less competitive in the West African sub-region, with a world ranking of 144th. It is therefore only natural to review certain parameters in order to improve this ranking. To do this, certain physico-chemical parameters of soil samples from Friguiagbé and Maferinyah (in the Kindia and Forécariah prefectures) were taken and analysed using the following techniques: Pipette de Robinson, Anne, Bray II, Kapen HICDVITZ, Mc. Lead (1982). The analytical results show that the soils at Friguiagbé in Kindia and Maferinyah in Forécariah are acidic, with pH values of 4.4 and 4.7 (fields I and II) and 4.8 and 4.7 (fields I and II) respectively. The soils have a silty-sandy texture. This study could therefore serve as a guide for the Ministry of Agriculture of the Republic of Guinea.

Consequences of Insufficient Selectivity in Quantitative and Qualitative Chemical Analysis

A problem in chemical analysis in connection with measurements of a substance normally occurring in a sample, or identification of a substance which should not exist in a sample, is insufficient selectivity. In this article, we analyze this problem and propose remedies. We use a real doping case to illustrate how chemical noise causes a serious selectivity problem, probably causing a false positive outcome.

Determination of creatinine level in patient blood samples by Fourier NIR spectroscopy and multivariate analysis in comparison with biochemical assay

In this paper,in vivo spectra from 23 patients'blood samples with various Creatinine(Cr)concentration levels ranging from 0.96 to 12.5 mg/dL were measured using Fourier transform near-infrared spectrometer(FT-NIRS)and spectrum quantitative analysis method.Since Cr undergoes passive filtration,it serves as a key biomarker of kidneys function via the estimation of glomerular filtration rate.Thus,increased blood Cr concentration reflects impaired renal func-tion.After spectra pre processing and outlier exclusion,a spectral model was developed based on partial least squares regression(PLSR)method,wherein Cr concentrations correlated with filtered NIR spectra across several peaks,where Cr is know n to absorb NIR light.Several statistical metrics were applied to estimate the model efficiency during data analysis.Comparison of spectra-derived concentrations to reference Cr measurements by the current gold-standard Jaffe's method held in hospital lab revealed a Cr prediction accuracy of 1.64 mg/dL with good corre-lation of R=0.9.Bland-Altman plots were used to compare between our calculations and ref-erence lab values and reveal minimal bias between the two.The finding presented the potential of FT-NIRS coupled with PLSR technique for Cr determination.

Blood gas analysis as a surrogate for microhemodynamic monitoring in sepsis

BACKGROUND:Emergency patients with sepsis or septic shock are at high risk of death.Despite increasing attention to microhemodynamics,the clinical use of advanced microcirculatory assessment is limited due to its shortcomings.Since blood gas analysis is a widely used technique reflecting global oxygen supply and consumption,it may serve as a surrogate for microcirculation monitoring in septic treatment.METHODS:We performed a search using PubMed,Web of Science,and Google scholar.The studies and reviews that were most relevant to septic microcirculatory dysfunctions and blood gas parameters were identified and included.RESULTS:Based on the pathophysiology of oxygen metabolism,the included articles provided a general overview of employing blood gas analysis and its derived set of indicators for microhemodynamic monitoring in septic care.Notwithstanding flaws,several parameters are linked to changes in the microcirculation.A comprehensive interpretation of blood gas parameters can be used in order to achieve hemodynamic optimization in septic patients.CONCLUSION:Blood gas analysis in combination with clinical performance is a reliable alternative for microcirculatory assessments.A deep understanding of oxygen metabolism in septic settings may help emergency physicians to better use blood gas analysis in the evaluation and treatment of sepsis and septic shock.

Chemical looping reforming of the micromolecular component from biomass pyrolysis via Fe_(2)O_(3)@SBA-16

To solve the problems of low gasification efficiency and high tar content caused by solid–solid contact between biomass and oxygen carrier in traditional biomass chemical looping gasification process.The decoupling strategy was adopted to decouple the biomass gasification process,and the composite oxygen carrier was prepared by embedding Fe_(2)O_(3) in molecular sieve SBA-16 for the chemical looping reforming process of pyrolysis micromolecular model compound methane,which was expected to realize the directional reforming of pyrolysis volatiles to prepare hydrogen-rich syngas.Thermodynamic analysis of the reaction system was carried out based on the Gibbs free energy minimization method,and the reforming performance was evaluated by a fixed bed reactor,and the kinetic parameters were solved based on the gas–solid reaction model.Thermodynamic analysis verified the feasibility of the reaction and provided theoretical guidance for experimental design.The experimental results showed that the reaction performance of Fe_(2)O_(3)@SBA-16 was compared with that of pure Fe_(2)O_(3) and Fe_(2)O_(3)@SBA-15,and the syngas yield was increased by 55.3%and 20.7%respectively,and it had good cycle stability.Kinetic analysis showed that the kinetic model changed from three-dimensional diffusion to first-order reaction with the increase of temperature.The activation energy was 192.79 kJ/mol by fitting.This paper provides basic data for the directional preparation of hydrogen-rich syngas from biomass and the design of oxygen carriers for pyrolysis of all-component chemical looping reforming.

Surface Analysis of Chemical Stripping Titanium Alloy Oxide Films

The chemical stripping method of titanium alloy oxide films was studied. An environment friendly solution hydrogen peroxide and sodium hydroxide without hydrofluoric acid or fluoride were used to strip the oxide films. The morphologies of the surface and cross-section of the oxide films before and after the films stripping were characterized by using scanning electron microscopy （SEM）. The microstructure and chemical compositions of the oxide films before and after the films stripping were investigated by using Raman spectroscopy （Raman） and X-ray photoelectron spectroscopy （XPS）. It was shown that the thickness of the oxide film was in the range of 5-6 μm. The oxide films were stripped for 2 to 8 min in the solution. Moreover, the effect of the stripping time on the efficiency of the film stripping was investigated, and the optimum stripping time was between 6-8 min. When the stripping solution completely dissolved the whole film, the α/β microstructure of the titanium alloy Ti-10V-2Fe-3Al was partly revealed. The stripping mechanism was discussed in terms of the dissolution of film delamination. The hydrogen peroxide had a significant effect on the dissolution of the titanium alloy anodic oxide film. The feasibility of the dissolution reaction also was evaluated.

Improved seismoacoustic analysis model and its application to source parameter inversion of near-surface small-yield chemical explosions

The seismoacoustic analysis method has broad potential applications to source parameter estimation for near-surface explosion events such as industrial explosions and terrorist attacks.In this study,current models were improved by modifying the acoustic model and adopting the Bayesian Markov-chain-Monte-Carlo inversion method.The source parameters of near-surface small-yield chemical explosions were analyzed via the improved seismoacoustic analysis model and by the estimation accuracy of seismoacoustic joint inversion.Estimation and analysis results showed that the improved seismoacoustic analysis model considered ground shock coupling and the impact of explosion products ejecting from the surface so that the improved acoustic impulse relation was more consistent with the measured data than the Ford impulse relation.It is suitable for deep-burial,shallow-burial,and near-surface aerial explosions.Furthermore,trade-off relationships were declined through the application of the improved model to source parameter inversion for near-surface small-yield chemical explosions,and source parameter estimation accuracy was improved.

Performance analysis of an O_2/ CO_2 power plant based on chemical looping air separation

The process of an O2//CO2 power plant based on chemical looping air separation （CLAS） is modeled using the Aspen Plus software. The operating parameters and power consumption of the CLAS unit are analyzed. The CLAS system, thermal power generation system and flue gas cooling and compression unit （CCU） are coupled and optimized, and the temperature and flow of the flue gas extraction are determined. The results indicate that the net plant efficiency of CLAS O2/CO2 power plant is 39.2%, which is only 3.54% lower than that of the conventional power plants without carbon capture. However, the O2/CO2 power plant based on cryogenic air separation technology brings 8% to 10% decrease in the net plant efficiency. By optimizations, the net plant efficiency increases by 1.65%. The energy consumption of the CCU accounts for 59.7% and the pump accounts for 27.1%. The oxygen concentration from the chemical looping air separation unit is 12.2%.

Research and Application of Computer Management of the Test Chemical Products Quality Analysis

According to the regulations of the People＇s Republic of China national standard as the basis, on the part of chemical industry product quality inspection and analysis of the implementation of computer management has developed a set of software applications, the software in chemical products quality inspection and analysis of the means of management is an innovation. The software functions, can automatically process data, judge the product grade, quality analysis, objective and fair, convenient, fast, accurate, stable, practical, and easy to popularize.

Feeding Study with Bt Corn (MON810: Ajeeb YG) on Rats: Biochemical Analysis and Liver Histopathology

Bt corn “MON810: Ajeeb YG” produces delta endotoxins in the whole plant due to the genetic modification process. The chemical analysis of this variety showed significant differences from its conventional counterpart “Ajeeb”. Further, feeding studies on rats were designed to complete assessing the safety of “MON810: Ajeeb YG”. Three groups of rats (6 males and 6 females’ rats/group) were fed on control diet, non-Bt corn and Bt corn for 1.5 months and 3 months. After 1.5 months, 3 males and 3 females from each group were sacrificed, and after another 1.5 months, 3 males and 3 females from each group and their offspring were sacrificed. Histopathological examination, blood haematology and serum biochemical analysis were determined. Results indicated significant differences among the tested parameters in the three groups especially Bt group. Severe changes in the liver of Bt group after 3 months were observed.

Source Apportionment of Ambient PM_(10) in the Urban Area of Longyan City,China:a Comparative Study Based on Chemical Mass Balance Model and Factor Analysis Method

In order to identify the day and night pollution sources of PM10 in ambient air in Longyan City,the authors analyzed the elemental composition of respirable particulate matters in the day and night ambient air samples and various pollution sources which were collected in January 2010 in Longyan with inductivity coupled plasma-mass spectrometry（ICP-MS）.Then chemical mass balance（CMB） model and factor analysis（FA） method were applied to comparatively study the inorganic components in the sources and receptor samples.The results of factor analysis show that the major sources were road dust,waste incineration and mixed sources which contained automobile exhaust,soil dust/secondary dust and coal dust during the daytime in Longyan City,China.There are two major sources of pollution which are soil dust and mixture sources of automobile exhaust and secondary dust during the night in Longyan.The results of CMB show that the major sources are secondary dust,automobile exhaust and road dust during the daytime in Longyan.The major sources are secondary dust,soil dust and automobile exhaust during the night in Longyan.The results of the two methods are similar to each other and the results will guide us to plan to control the PM10 pollution sources in Longyan.

Syngas production from chemical looping reforming of ethanol over iron-based oxygen carriers: Theoretical analysis and experimental investigation

Chemical looping reforming(CLR)is a recent trend for syngas production,which has several merits compared to the conventional manner.One of the most important issues for CLR is to find low-cost material as oxygen carriers,so iron is a promising candidate.This paper contributes to testing the thermodynamic ability of iron-based oxygen carrier for chemical looping reforming of ethanol(CLRE).Iron thermodynamically investigated in temperature 100–1300℃and excess oxygen number(φ)0–4.It was found that the temperature andφhave an apparent effect on the gaseous composition produced from the process.Increases in temperature within the range of 100–1300℃enhanced syngas generated and reduced coke formation and CH4.Whereas,increasedφ,particularly at higher temperatures,had also enhanced syngas production as well as reduced coke formation.However,increasingφfor values beyond one had decreased syngas and not significantly reduced coke deposition.Moreover,an experimental investigation was carried out in a fixed bed reactor for more in-depth verification of iron ability as an oxygen carrier through using magnetite ore(mainly Fe3O4).It found that the effect of temperature on syngas production was consistent with that calculated thermodynamically,as syngas increased with raising the temperature through the CLRE.

Structure Analysis for Hydrate Models of Ethyleneimine Oligomer by Quantum Chemical Calculation

Structure analyses for hydrate models of ethyleneimine oligomer (5-mer as model of PEI) were investigated by quantum chemical calculations. Conformation energies and structures optimized for hydrate models of (ttt)5 and (tgt)5 conformers were examined. Hydrate ratio, h [h = H2O/N (mol)], was set from 0.5 to 2. In anhydrates, (tg+t)5 conformer was more stable (?1.8 kcal/m.u.) than (ttt)5. In hydrates, (ttt)5 conformers were more stable (?0.7 - ?4.3) than (tg+t)5. These results corresponded to experimental results that anhydrous linear PEI crystal changes from double helical to single planar chain in hydration process. Structures calculated for (ttt)5 agreed in those observed for hydrates of PEI. In all (tg+t)5 conformers, O???H bonds between waters were found with the decreases of N???H bonds between imino group and water. The O???H bonds in (tg+t)5 conformer resulted in its high chain torsion, and strongly related with instability and structure change (large swelling).

Intelligent Management Based on Chemical Reagent Quality Analysis

Access database technology and Visual Basic programming language are used to develop a set of chemical reagents quality analysis and inspection of intelligent management application software, and its stability was investigated. The results show that the sotfware is used to manage intelligently the quality analysis of chemical reagents test each linkage, to upload and save the analysis of test data and results in the network in time for users, to build a network of information sharing platform for enterprises and quality management departments, and its quality of chemical reagents test results is used to manage by the computer with practical application value. The software is simple, convenient, fast, friendly interface, stable operation, accurate and reliable results, with a high value to promote the application.

Chemical Analysis Method for Carbon Bearing Refractory Products——Determination of the Total Carbon by Combustion Gravimetric Method

GB/T 13245-91 1 Theme and Scope This standard specifies the method abstract, reagents, apparatus, specimen, analyzing procedure, result calculation and permissible tolerance used for determination of the total carbon with combustion gravimetric method.

Chemical Analysis Method for Magnesia and Magnesia-Alumina Refractories——Gravimetric-Molybdenum Blue Photometric Method for Determination of Silicon Dioxide Content

This standard specifies the gravimetric-molybdenum blue photometric method for determination of silicon dioxide content.

Chemical Analysis of Water and the Resource of Br,K Prospects of Oilfield Brines from Ordovician and Carboniferous in Tarim,China

China is lack of bromine and potassium seriously.Oilfield brines is the headline goal of bromine and potassium resources exploration.Applicants grab 24oilfield brines samples from various wells of Ordovician

A tool model for predicting atmospheric chemical kinetics with sensitivity analysis

A package(a tool model) for program of predicting atmospheric chemical kinetics with sensitivity analysis is presented. The new direct method of calculating the first order sensitivity coefficients using sparse matrix technology to chemical kinetics is included in the tool model, it is only necessary to triangularize the matrix related to the Jacobian matrix of the model equation. The Gear type procedure is used to integrate a model equation and its coupled auxiliary sensitivity coefficient equations. The FORTRAN subroutines of the model equation, the sensitivity coefficient equations, and their Jacobian analytical expressions are generated automatically from a chemical mechanism. The kinetic representation for the model equation and its sensitivity coefficient equations, and their Jacobian matrix is presented. Various FORTRAN subroutines in packages, such as SLODE, modified MA28, Gear package, with which the program runs in conjunction are recommended. The photo\|oxidation of dimethyl disulfide is used for illustration.

AI_4C_3 Hydration Thermochemical Analysis for Burned Carbon-containing Refractories with Al

In this paper, X-ray diffractogram analysis and SEM observation of Al$ C$ formed at high temperature from carbon-containing refractories ivith Al have been carried out. Aluminum added to carbon-containing refractories reacts with C（s） to form Al^ C^（s） gradually during heating from 600 ’C to 1200^0 . It is considered that the interlocked structure of Al^ C-$ plate crystals promotes the outstanding increase of hot modulus of rupture of carbon-containing refractories with Al. The HMOR of carbon-containing refractories added with Al additive from 0 to 5wt% increases by 2.8 times being from 6.5MPa to 18.2MPa. After a thermochemical calculation for hydration reaction processes ofAl^C^ and H^O （g）, the equilibrium partial pressure chart ofH^O （g） in H^O-A^C^-Al^ OH)} system vs various temperatures has been attained . The H2 0 （g） partial pressure in the air needed for the Al^ C3 hydration reaction is no more than 10;18 atm at the temperature below 120t . It is considered that the burned carbon-containing re