Apparent activation energy for spontaneous combustion of sulfide concentrates in storage yard

In order to evaluate the spontaneous combustion hazard of sulfide concentrates in storage, three different kinds of sulfide concentrates （sulfur-rich sulfide concentrate, iron sulfide concentrate and copper sulfide concentrate） were obtained from a storage yard in Dongguashan Copper Mine, China. The reaction processes at different heating rates of 5, 10, 15, 20, and 25 ℃/min in air flow from ambient temperature to 1 000 ℃ were studied by TG-DTG-DSC analysis. By the peak temperatures of DTG curves, the whole reaction process for each sample was divided into different stages, and the corresponding apparent activation energies were calculated by the Ozawa-Flynn-Wall method. It is found that the reaction process of each sample is considerably complex; the apparent activation energy values change from 36 to 160 kJ/mol in different temperature ranges; sulfur-rich sulfide and iron sulfide concentrates have lower apparent activation energy than copper sulfide concentrate below 150 ℃; so they are more inclined to cause spontaneous combustion at ambient temperature.

Two clinically relevant pressures of carbon dioxide pneumoperitoneum cause hepatic injury in a rabbit model

AIM:To observe the hepatic injury induced by carbon dioxide pneumoperitoneum(CDP) in rabbits,compare the eects olow-and high-pressure pneumoperitoneum,and to determine the degree o hepatic injury induced by these two clinically relevant CDP pressures.METHODS:Thirty healthy male New Zealand rabbits weighing 3.0 to 3.5 kg were randomly divided into three groups(n = 10 for each group) and subjected to the ollowing to CDP pressures:no gas control,10 mmHg,or 15 mmHg.Histological changes in liver tissues were observed with hematoxylin and eosin staining and transmission electron microscopy.Liver unction was evaluated using an automatic biochemical analyzer.Adenine nucleotide translocator(ANT) activity in liver tissue was detected with the atractyloside-inhibitor stop technique.Bax and Bcl-2 expression levels were detected bywestern blotting.RESULTS:Liver Functions in the 10 mmHg and 15 mmHg experimental groups were significantly disturbed compared with the control group.After CDP,the levels or alanine transaminase and aspartate transaminase were 77.3 ± 14.5 IU/L and 60.1 ± 11.4 IU/L,respectively,in the 10 mmHg experimental group and 165.1 ± 19.4 IU/L and 103.8 ± 12.3 IU/L,respectively,in the 15 mmHg experimental group,which were all higher than those of the control group(p < 0.05).There was no difference in pre-albumin concentration between the 10 mmHg experimental group and the control group,but the prealbumin level of the 15 mmHg experimental group was significantly lower than that of the control group(p < 0.05).No significant differences were observed in the levels of total bilirubin or albumin among the three groups.After 30 and 60 min of CDP,pH was reduced(p < 0.05) and fa CO2 was elevated(p < 0.05) in the 10 mmHg group compared with controls,and these changes were more pronounced in the 15 mmHg group.Hematoxylin and eosin staining showed no significant change in liver morphology,except for mild hyperemia in the two experimental groups.Transmission electron microscopy showed mild mitochondrial swelling in hepatocytes of the 10 mmHg group,and this was more pronounced in the 15 mmHg group.No significant difference in ANT levels was found between the control and 10 mmHg groups.However,ANT concentration was significantly lower in the 15 mmHg group compared with the control group.The expression of hepatic Bax was significantly increased in the two experimental groups compared with the controls,but there were no differences in Bcl-2 levels among the three groups.Twelve hours after CDP induction,the expression of hepatic Bax was more significant in the 15 mmHg group than in the 10 mmHg group.CONCLUSION:A CDP pressure of 15 mmHg caused more substantial hepatic injury,such as increased levels of acidosis,mitochondrial damage,and apoptosis;therefore,10 mmHg CDP is preferable for laparoscopic operations.

An improved TF-IDF approach for text classification

This paper presents a new improved term frequency/inverse document frequency (TF-IDF) approach which uses confidence, support and characteristic words to enhance the recall and precision of text classification. Synonyms defined by a lexicon are processed in the improved TF-IDF approach. We detailedly discuss and analyze the relationship among confidence, recall and precision. The experiments based on science and technology gave promising results that the new TF-IDF approach improves the precision and recall of text classification compared with the conventional TF-IDF approach.

Baicalin and geniposide inhibit the development of atherosclerosis by increasing Wntl and inhibiting dickkopf-related protein-1 expression

Background Our previous study showed that the combined Chinese herbs containing scutellaria baicalensis georgi and gardenia jasminoids ellis inhibited atherosclerosis. In this study, we sought to determine if baicalin and geniposide could inhibit atherosclerosis through Wntl and dickkopf-related protein-1 （DKK1）. Methods The wild-type and ApoE-/- mice were treated with baicalin, geniposide, and baicalin plus geniposide daily by gavage for 12 weeks. Blood lipid levels were measured with an automatic biochemistry analyzer. Aortic atherosclerotic lesion areas were analyzed with Image-ProPlus software. The mRNA and protein expression of DKK1, Wntt and nuclear factor-r,B （NF-κB） were measured with RT-PCR and Westem Blot. Serum levels of interleukin-12 （IL-12） were quantified with ELISA. Results The baicalin or geniposide monotherapy as well as combination therapy inhibited the development of atherosclerotic lesions, increased Wntl and decreased DKKI expression and elevated the ratio of Wntl/DKK1 compared with high-lipid diet group. However, only baicalin or geniposide monotherapy decreased NF-κB expression. Moreover, baicalin and geniposide monoor combination therapy lowered IL-12 levels. Geniposide reduced both serum total cholesterol and low density lipoprotein levels, while baicalin either alone or in combination with geniposide did not affect serum lipid levels. In human, umbilical vein endothelial ceils stimulated by oxidized low density lipoprotein, baicalin and geniposide also increased Wntl and decreased DKK1 expression and elevated the ratio of Wntl/DKK1. Condusions Baicalin and geniposide exert inflammation-regulatory effects and may prevent atherosclerotic lesions through enhancing Wntl and inhibit- ing DKK1 expression.

Urban Expansion in China Based on Remote Sensing Technology：A Review

Urban areas and its evolution are important anthropogenic indicators and human ecological footprints, and play decisive roles in environmental change analysis, global geo-conditional monitoring, and sustainable development. China has the highest rate of urban expansion and has emerged as an urban expansion hotspot worldwide. In this paper, the progress of studies on Chinese urban expansion based on remote sensing technology are summarized and analyzed from the aspects of urban area definition, remotely sensed imagery applied in urban expansion, monitoring methods of urban expansion, and urban expansion applications. Existing issues and future directions of Chinese urban expansion are discussed and proposed. Results indicate that: 1) The fusion of multi-source remotely sensed imagery is imperative to meet the needs of urban expansion with various monitoring terms and frequencies on different scales and dimensions. 2) To guarantee the classification accuracy and efficiency and describe urban expansion and its influences on local land use simultaneously, the combination of visual interpretation and automatic classification is the tendency of future monitoring methods of urban areas. 3) Urban expansion data have become the prerequisite for recognizing the urban development process, excavating its driving forces, simulating and predicting the future development directions, and also is conducive to revealing and explaining urban ecological and environmental issues. 4) In the past decades, Chinese scholars have promoted the application of remote sensing technology in the urban expansion field, with data construction, methods and models developing from the quotation stage to improvement and innovation stage; however, an independent and consistent urban expansion data on the national scale with long-term and high-frequency(such as annual monitoring) monitoring is still lacking.

Non-invasive glucose measuring apparatus based on conservation of energy method

A new non-invasive blood glucose measuring apparatus (NBGMA) made up of MSP430F149 SCM (single chip micyoco) was developed,which can measure blood glucose level (BGL) frequently,conveniently and painlessly. The hardware and software of this apparatus were designed,and detecting algorithms based on conservation of energy method (COEM) were presented. According to the law of conservation of energy that the energy derived by human body equals energy consumed by metabolism,and the relationship between convection,evaporation,radiation and the BGL was established. The sensor module was designed. 20 healthy volunteers were involved in the clinical experiment. The BGL measured by an automatic biochemical analyzer (ABA) was set as the reference. Regression analysis was performed to compare the conservation of energy method with the biochemical method,using the 20 data points with blood glucose concentrations ranging from 680 to 1 100 mg/L. Reproducibility was measured for healthy fasting volunteers. The results show that the means of BGL detected by NBGMA and ANA are very close to each other,and the difference of standard deviation (SD) is 24.7 mg/L. The correlative coefficient is 0.807. The coefficient of variation (CV) is 4% at 921.6 mg/L. The resultant regression is evaluated by the Clarke error grid analysis (EGA) and all data points are included in the clinically acceptable regions (region A:100%,region B:0%). Accordingly,it is feasible to measure BGL with COEM.

A Signal-Flow Driven Automatic Physical Synthesis Methodology for Analog Circuits

This paper introduces a novel automatic physical synthesis methodology for analog circuits based on the signal-flow analysis.Circuit analysis sub-system adopts the newly advanced methodology,circuit topology analysis,and circuit sensitivity analysis to generate layout constraints and control performance degradations.Considering the heuristic information about signal-flow,complexity of the methodology is less than the pure performance-driven methodology.And then these constraints are implemented in device generation,placement,and routing sub-systems separately,which makes the different constraints be satisfied at most easily implemented stages.Excellent circuit performance obtained by the methodology is demonstrated by practical circuit examples.

Effects of low dose pre-irradiation on the toxicity of cyclophosphamide

Objective:The aim of the study was to investigate the effects as well as the possible mechanisms of low dose γ-ray pre-irradiation on hepatic damage,DNA damage of peripheral lymphocytes and genetic material damage caused by high dosage of cyclophosphamide(CTX).Methods:Kunming strain male mice were randomly divided into five groups:control group,sham-irradiated group,low dose irradiation group(LDR group),cyclophosphamide chemotherapy group(CTX group) and low dose irradiation combined with chemotherapy group(LDR + CTX group).Having being raised for one week,all the mice were implanted subcutaneously with S180 cells in the left inguen(control group excluded).On days 8 and 11,mice of LDR and LDR + CTX groups were given 75 mGy whole-body γ-irradiation,30 h later mice of CTX and LDR + CTX groups were injected i.p.3.0 mg cyclophosphamide.All the mice were sacrificed on day 13.DNA damage of the peripheral lymphocytes was analyzed using single cell gel electrophoresis(SCGE);ALT activity,total protein(TP) and albumin(ALB) of the plasma were analyzed using automatic biochemistry analyzer;MDA content,SOD and GSH-PX activity of the hepatic homogenate were analyzed using chromometry;genetic material damage was analyzed using micronucleus frequency(MNF) of polychromatoerythrocytes(PCE) in bone marrow.Results:1.Differences of MDA contents,SOD and GSH-PX activity of hepatic homogenate between 5 groups had notable statistical significance(P < 0.01);in control group MDA content was the lowest,SOD and GSH-PX activity were the highest,while in CTX group MDA content was the highest,SOD and GSH-PX activity were the lowest;compared with CTX group MDA content decreased significantly(P < 0.01) and SOD and GSH-PX activity increased significantly(P < 0.05) in LDR + CTX group.2.Differences of ALT activity of plasma between 5 groups had no statistical significance(F = 1.262,P > 0.05).Differences of TP and ALB of plasma between 5 groups had statistical significance(F = 12.879 and 6.336 respectively,P < 0.01);TP and ALB in control group were higher than those of other groups and compared with sham-irradiated group,TP and ALB in LDR group elevated significantly(P < 0.05).3.Differences of DNA damage of peripheral lymphocytes had notable statistical significance(F = 6.383,P < 0.01);DNA damage in control group was the lightest,while DNA damage in CTX group was the severest;compared with CTX group,DNA damage in LDR + CTX group was much lighter(P < 0.05).4.MNF of PCE between 5 groups had remarkable significance(F = 179.652,P < 0.01);compared with control group and sham-irradiated group,MNF in CTX group increased significantly(P < 0.01);compared with CTX group,MNF in LDR + CTX group had a tendency of decline,which had no statistical significance(P > 0.05).Conclusion:1.CTX can damage the hepatic tissue through oxidative stress;75 mGy γ-irradiation before CTX chemotherapy can induce activities of anti-oxidative enzymes,promote elimination of free radicals,so as to alleviate the damaging effects of oxidative stress to hepatic tissue caused by high-dose chemotherapy.2.A 75 mGy γ-irradiation before CTX chemotherapy has no obvious effect on ALT activity of plasma,but may have protective effect on the protein synthesis function of liver.3.High-dose CTX chemotherapy can cause DNA damage of peripheral lymphocytes;75 mGy γ-irradiation before chemotherapy may have certain protective effect on DNA damage.4.CTX has potent mutagenic effect,can cause significant increase of MNF of PCE;75 mGy γ-ray pre-irradiation did not show obvious protection against genetic toxicity of high-dose CTX chemotherapy.

Rate Constants for Reaction Between Hydroxyl Radical and Dimethyl Sulfide Under Real Atmospheric Condition

The rate constants of the reaction between hydroxyl radical （OH-） and dimethyl sulfide （DMS） were investigated by using the relative methods in air, N2, and 02. Strong influences of ground state oxygen O（3p） on DMS consumption were found by the photolysis of HONO and CH3ONO as OH. sources, and the rate constants obtained in these systems varied significantly. The rate constants of the reaction between DMS and OH- （generated by photolysis of H2 O2） at room temperature were 8.56 × 10^-12, 11.31× 10^-12, and 4.50× 10^-12 cm3/（molecule.s）, in air, O2, and N2, respectively. The temperature dependence of the rate constants for OH- with DMS over the temperature range of 287-338 K was also investigated in nitrogen and air, and the Arrhenius expression was obtained as follows： kaire=（7.24±0.28）× 10^-13exp[（770.7±E97.2）/T], kN2 =（3.40±0.15） × 10^-11 exp[-- （590.3±165.9）/T].

Automatic Analysis Reporting for Hydro-Chemical Data Using Updated DurovPwin Program

Graphical representation of groundwater major dissolved constituents greatly help researchers in understanding the hydro-chemical evolution, grouping and areal distribution. Durov diagram is one of the most widely used technique but it requires a lot of tedious calculations. The DurovPlot program, which is used to plot the expanded Durov diagram as a graphical representation of groundwater major dissolved constituents is working on Disk Operating System （DOS） environment. Therefore, the need of a new program working under windows is a must. The program termed as DurovPwinis developed using Microsoft visual studio 2010. The DurovPwin program not only calculates the Durov coordinates and plot it, but also plots the total dissolved solids （TDS） on logarithmic scale and the measure of the activity of hydrogen ion （pH） of the given samples. The updated DurovPwin adds many features such as interface with Microsoft Office package （Word and Excel） to read the input chemical elements and automatically write result interpretation report. The user facility to group wells based on data features is added and the selection of the electric balance tolerance （10% as default） value is given. Another feature of the modified DurovPwinis has the ability to do useful X-Y plot for different hydro-chemical parameters to assist in data interpretation. The sodium adsorption ratio （SAR） is also calculated and written in the final report. Also, in the present study, the usability of the new version of DurovPwin program has been tested on the chemical data from 59 groundwater samples collected from A1-Jawf area, Saudi Arabia. The collected water samples were mainly from the Secondary-Tertiary-Quaternary （STQ） aquifer and some from Tawil and Jaufaquifers. The grouping of the major ions in the three aquifers have been displayed and presented using the DurovPwin program. The TDS values of Tawil aquifer ranges from 257.9 to 822.3 （2.4115 to 2.915） and for Jawf aquifer from 494.4 to 1,070 （2.6941 to 3.0294） and for STQ aquifer ranges from 399.5 to 9,861.8 （2.6015 to 3.994）. The pH for the three aquifers ranges from 7 to 7.9, 7.6 to 7.8 and 7.2 to 8.3, respectively.

Sentiment classification model for bullet screen based on self-attention mechanism

With the development of short video industry,video and bullet screen have become important ways to spread public opinions.Public attitudes can be timely obtained through emotional analysis on bullet screen,which can also reduce difficulties in management of online public opinions.A convolutional neural network model based on multi-head attention is proposed to solve the problem of how to effectively model relations among words and identify key words in emotion classification tasks with short text contents and lack of complete context information.Firstly,encode word positions so that order information of input sequences can be used by the model.Secondly,use a multi-head attention mechanism to obtain semantic expressions in different subspaces,effectively capture internal relevance and enhance dependent relationships among words,as well as highlight emotional weights of key emotional words.Then a dilated convolution is used to increase the receptive field and extract more features.On this basis,the above multi-attention mechanism is combined with a convolutional neural network to model and analyze the seven emotional categories of bullet screens.Testing from perspectives of model and dataset,experimental results can validate effectiveness of our approach.Finally,emotions of bullet screens are visualized to provide data supports for hot event controls and other fields.

The Relevance of CARICOM＇s Existence to the Virgin Islands in the Context of Globalization

The purpose of this study was to consider the relevance of CARICOM＇s existence to the Virgin Islands （BVI）. Its relevance becomes more significant to the BVI and the Caribbean, by extension, when the globalization phenomenon is applied; a phenomenon that has been in existence for centuries. Overall, the study concluded that even though the BVI remains only an associate member of CARICOM and not of CSME, it still has an interest in the progress of the regional grouping and its trade initiatives. Over the years, CARICOM has been struggling with its identity as a unified grouping. Nonetheless, it was found that in an effort to combat the trade liberalization process, the grouping must find that inner connection to advance its agenda on the global stage. Accordingly, it has been suggested that CARICOM begin to focus on its strengths and opportunities in order for economic development across the region to occur. It has also been recommended that more serious considerations be taken towards the development of a comprehensive regional market for the trading of goods and services, that is, the Caribbean Single Market and Economy （CSME）. To substantiate its findings, the paper used the qualitative research approach, combined with a situation （SWOT） analysis.

Monitoring Ambient Air Quality in the Carpathian Region of Ukraine

Ivano-Frankivsk oblast is located in the south-western part of Ukraine, close to the geographical center of Europe at the junction of the two major geographic units, the East European Plain and the Eastern Carpathians （the Carpathian region of Ukraine）. Between September 2013 and September 2015, the expert group of the Department of Organic and Analytical Chemistry of Vasyl Stefanyk Precarpathian National University conducted the mobile monitoring of air cleanliness in Ivano-Frankivsk region; the authors monitored the level of air contamination with seven gases： carbon monoxide and dioxide, sulfur dioxide, nitrogen dioxide, hydrogen sulfide, ammonia, formaldehyde, beta-particles, and gamma radiation. For this purpose, there were used six automatic analyzers ＂Dozor-C-P＂, the formaldehyde Gas Analyzer ＂MIC-98170＂, and the radiometer ＂TERRA＂. The monitoring resulted in the making of three maps of Ivano-Frankivsk region, on which the average levels of concentration of three particular gases （CO2, SO2, and CH20） throughout all the districts of the oblast were marked. There was registered the excess of CH20 limits--the consequences of the presence of the chipboard and wood-fiber production, for which formaldehyde is used as a raw material. Also there was observed the excess of SO2 in the air caused by gas fumes from vehicles and thermal power stations.

Web-Based Synthetic Optimization Design System of Micro-Components

In order to meet the requirement of network synthesis optimization design for a micro component, a three-level information frame and functional module based on web was proposed. Firstly, the finite element method （FEM） was used to analyze the dynamic property of coupled-energy-domain of virtual prototype instances and to obtain some optimal information data. Secondly, the rough set theory （RST） and the genetic algorithm （GA） were used to work out the reduction of attributes and the acquisition of principle of optimality and to confirm key variable and restriction condition in the synthesis optimization design. Finally, the regression analysis （RA） and GA were used to establish the synthesis optimization design model and carry on the optimization design. A corresponding prototype system was also developed and the synthesis optimization design of a thermal actuated micro-pump was carded out as a demonstration in this paper.

A Spatialization-based Method for Checking and Updating Metadata

In this paper the application of spatialization technology on metadata quality check and updating was dis-cussed. A new method based on spatialization was proposed for checking and updating metadata to overcome the defi-ciency of text based methods with the powerful functions of spatial query and analysis provided by GIS software. Thismethod employs the technology of spatialization to transform metadata into a coordinate space and the functions ofspatial analysis in GIS to check and update spatial metadata in a visual environment. The basic principle and technicalflow of this method were explained in detail, and an example of implementation using ArcMap of GIS software wasillustrated with a metadata set of digital raster maps. The result shows the new method with the support of interactionof graph and text is much more intuitive and convenient than the ordinary text based method, and can fully utilize thefunctions of GIS spatial query and analysis with more accuracy and efficiency.

Energy analyses for the energetically self-sufficient supercritical water oxidation process

One of the bottle-neck problems to the commercial development of supercritlcal water oxidation （SCWO） is high operation cost. In this study the condition to realize an energetically self-sufficient SCWO process is analyzed. The reaction heat is recovered by means of Organic Rankine Circle. The process of SCWO for phenol is simulated with the Aspen Plus~ process simulator, and the results show that the influence of temperature on reaction heat is small at a constant pressure. It is reasonable to neglect the effect of temperature and to estimate the heat of reaction with average temperature when the temperature changes in a small range. The necessary condition to realize an energetically self-sufficient SCWO process is that the released energy is not less than consumed one. Whether a waste system with given chemical composition is energeticallyself-sufficient can be estimated by ^QR^QH 〉 W The thermodynamics analysis shows that energetically self-sufficient SCWO process with an Organic Rankine Cycle is a feasible technology for the recovery of SCWO reaction heat,and the energy balance point for phenol is 2wt%.

Analysis of Cutting Force by End Milling Using Artificial ntelligence

The cutting forces during end milling process by using Genetic Algorithm are investigated in this paper. However, automated CNC （computer numerical control） programming by milling machine is intended to use for special required conditions of programming of tool path length, and analysis of cutting force and optimization of main parameters are presented. Some effective simplification of automated programming is done for cutting force. The cutting force is modelled and analyzed into mathematical simulations in order to optimize the main cutting parameters, also in this case tool path length, it is get as free trajectory. Optimization is carried out by using the Matlab/Genetic Algorithm method that excessively reduce the time and to optimize the main cutting parameters of machining. The number of experiments, measurements and results of cutting force （F~）, are presented in 3D as well as in tables. In order to verify the accuracy of the 3 D simulation with optimization method, the results are compared in experimental and theoretical way. In other word, these results indicate directly that the optimized parameters are capable of machining the workpiece. Achieved results that are presented in this paper may in general help the new researcher as well as manufacturing industries of metal cutting.

Detection and Quantitative Analysis of Dominant Bacteria On Aging Flue-cured Tobacco Leaves

[Objective] The aim was to construct the internal motivation of flued-cured tobacco natural aging. [Method] The variation of DNA copies of Bacillus megaterium, amylase activity, PPO, peroxydase and content of starch, neutro-protein, polyphenol in different aging period were investigated using Henan flue-cured tobacco leaves. [Result] Results showed that the DNA copies of Bacillus megaterium increased initially but decreased subsequently with the aging time. The DNA copies of Bacillus per gram of tobacco leaf surface reached the maximum number at 6 months aging. The activities of four enzymes showed the same variation trend as in DNA copies, and also reached the highest level at 6 months aging. Chemical ingredients, however, displayed a downward trend. The variation of enzyme activity and content of chemical composition were reflected in the changes of DNA copies in Bacillus megaterium. [Conclusion] The result indicate that Bacillus megaterium was the internal motivation of flue-cured tobacco natural aging.

Dynamic Analysis of the Biped Ice-skater Robot of Passive Wheel Type

A new passive wheel type of biped ice-skater robot (BISR) subjected to nonholonomic constraints was presented on the basis of ice-skating principle. Its motion principle and construction were discussed. After the model was simplified and the coordinate systems were established, the motion differential equations of the robot were obtained with the generalized Lagrange-Maggi equation when the nonholonomic constraints existed. Actual examples were given and the result was simulated on computer.