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air-fuel equivalence ratio and timescales of kinetic reaction and oxygen transport were used to analyze the combustion of underground coal fires at different temperature stages. At high temperature stage, due to the fast rate of kinetic reaction, oxygen concentration transported from galleries or cracks was lower than that required by theoretical kinetic reaction. Thus the oxygen consumption rate of coal combustion was controlled by oxygen transport rate and the coal fires were incomplete combustion because of lean oxygen concentration. According to the Single-Particle Reaction- Diffusion model proposed by Krishnaswamy, a formula to estimate oxygen consumption rate of underground coal fires with lean oxygen concentration and incomplete combustion at high temperature was developed. A numerical case study was conducted to analyze and examine the proposed formula. The investigated results show that the proposed formula can effectively estimate oxygen consumption rale controlled by oxygen transport at high temperature. [ABSTRACT FROM AUTHOR]

In order to study damage deformation of low permeability and soft coal under pulsating water pressure, the experiment of different maximal pulsating water pressure acting on standard raw coal was done by using the RLW-2000M coal rheometer controlled by microcomputer. The results show that the strain curve can be characterized by three phases when the samples are damaged by pulsating pore-pressure. In the initial stage, that is compaction coupling phase, the strain curve will generate large deformation in the process of loading and unloading, so the hysteresis loop curve will not be formed. In the elastic coupling phase, the strain curve demonstrats a stable hysteresis loop curve. In the yield deformation phase, coal will generate fatigue failure after several large deformation. The deformation state of elastic coupling phase was determined by using energy dissipation, and the results show that the coal unit produces plastic deformation and damage after a cycle of pulsating water pressure. At last, on the basis of Logistic equation, the mathematical model of coal damage was established and the unknown parameters were calculated by fitting analysis. [ABSTRACT FROM AUTHOR]

To analyze the oxidation kinetics reason that self-ignition tendency of coal with different metamorphic degree are different, based on the basic assumptions of coal adiabatic self-heating process, a oxidation kinetics analysis on the reaction characteristics of the process was made combined with the Arrhenius equation, then this paper studied four feature parameters: adiabatic process apparent activation energy (Ec), the critical temperature ( Tc) and the average heating rates each stages of the adiabatic process, (Rhm,Rjs), finally, the relationship between each characteristic parameter and coal metamorphic level was made by numerical fitting. It is show that the oxidation kinetics characteristics are characterized by the four parameters (Ec, Tc, Rhm and Rjs) in the difficulty degree of coal self-ignition reaction (Ec),the difficulty degree of control ( Tc) and the heating speed (Rhm and Rjs) ;with the increase of coal metamorphic grade, Ec has a logarithmic relation with it, Tc has a linear relation, however, Rhm and Rjs have a negative exponent relation. The difference of self-ignition tendency of coal with different metamorphic degree is studied on oxidation kinetics, and it is of great significance to self-ignition control. [ABSTRACT FROM AUTHOR]

Due to spontaneous combustion of coal stockpile on surface ground had been a serious problem with the stock quantity and stock time increased, a temperature measuring technology applied to prevent and control the spontaneous combustion of coal stockpile became a necessary means. The paper firstly stated the available direct and indirect coal stockpile temperature measuring methods and principle. Then the paper introduced the common simple temperature measuring device and the composite type temperature measuring equipment of coal stockpile, and analyzed the structural principle, advantages and disadvantages, as well as the application scope. The results showed that a wireless temperature measuring and optical fiber temperature measuring technology would be the research focuses of present temperature measuring for coal stockpile, the precision, complex and automation of the temperature measuring system would be the development tendency, the development of coal stockpile temperature measuring instrument based on new mechanism would be a new development orientation. [ABSTRACT FROM AUTHOR]

To investigate the characteristics of adiabatic oxidation phase and build the prediction model of coal spontaneous combustion critical point, the adiabatic oxidation experiment data of eight coal samples are given in this paper, based on the adiabatic oxidation experiment, element analysis experiment and industrial analysis experiment. The phase heating rates of adiabatic oxidation of these samples are also calculated. Then using the thermodynamic parameter calculation method, Tr0.05 and TΔmax are defined and obtained. Furthermore, based on the Levenberg-Marquardt method, the relationship between the coal element content, volatility, the phase heating rate of adiabatic oxidation and Tr0.05 are established. The results show that the content of N or S correlates positively with Tr0.05 Osand that O, C, or H content correlates negatively with Tr0.05. However, the link between these elements and stage-heating rate is the opposite. The law also suggests that stage-heating rate will be much faster and coal spontaneous combustion will be easier when Tr0.05 becomes much lower. The more volatile coal is, the lower Tr0.05, and the more likely it is to spontaneously combust. [ABSTRACT FROM AUTHOR]

Aiming at the problems of buried tube nitrogen injection that the nitrogen injection spot with intervals in the space causes the failure of continuous nitrogen distribution in goaf, leading to poor inert effect. In addition, the unrecycling of the nitrogen injection pipe causes great resources waste. Based on the principle that the shear capacity of the mining nitrogen injection pipe is superior to its tensile strength, new fire nitrogen injection process (rotating traction and non-interval) was designed, fundamentally solving major defects of buried pipe nitrogen injection, which can realize the synchronous movement between nitrogen injection point and the workface. According to the relevant principles of planar problems in elastic mechanics, the calculation method about dynamic parameter of non-interval nitrogen injection process for fire control was put forward. By using a geotechnical engineering numerical simulation software, the stress distribution of the nitrogen injection pipe in the goaf of Yanzishan Mine was simulated, and the traction power was computed based on it. [ABSTRACT FROM AUTHOR]

In order to theoretically understand the law of temperature rise due to spontaneous combustion in caving zone of roof coal in coal mine roadway, and identify the location of hazardous region and studied the fire prevention effects by nitrogen injection, the software FLUENT was used to solve the stable state of air leakage speed and oxygen concentration ,dynamic temperature distribution and cooling effects brought by nitrogen injection in the high caving zone based on the assumption that coal oxidation rate accords with Arrhenius law. The computation results indicate that the temperature rise reflects a slow-accelerating process and the portion close to roadway has lowest temperature while the deep portion comes next, the top temperature region lies in the middle part of caving zone and deviates to inlet. The rate of temperature rise in high temperature region accelerates both by the increasing air velocity in roadway and increasing porosity when practical size is kept unchanged. The nitrogen injection in high temperature region can lead to obvious cooling effects for the reason that the temperature close to injection hole decreases dramaticlly after short time and cooling effects extend towards part of the middle and outlet gradually. [ABSTRACT FROM AUTHOR]

The gas pressure gradient variation law and the horizontal ground stress distribution law of the tectonic outburst seam would be the major factor affected to the coal and gas outburst. A quantitative calculation model of the seam gas pressure gradient and horizontal ground stress was established. Taking the regional tectonic outburst seam near No. 236-80 north cross-cut in Tanjiachong Mine as a study object, the FLAC simulation result showed that the seam failure was serious in the region with horizontal ground stress approached to zero. The calculation showed that when the ground stress was about 3 MPa, the gas pressure gradient in the tectonic seam would have a sudden change. When the horizontal ground stress was over 3 MPa, the gas pressure gradient would rapidly increase in the two regions of 0-5 m and 42-62 m along the strike direction of the seam physical model. [ABSTRACT FROM AUTHOR]

According to the problem that a large number of residual coal left in the goaf of the resources integration mine because of the early extensive mining, which was easy to cause spontaneous combustion of coal. Taking No. 4+9 coal seam of Beizu Coal Mine as a study subject, the combustion situation of fire area was researched through indicator gas experiment, and the high-temperature area of the roadway roof face was divided through infrared detection technique. The result showed that, CO C2H4 and C2H6 could be taken as the indicator gas for spontaneous combustion in No. 4+9 coal seam of Beizu Coal Mine, the temperature in fire area was 80~110 ⋅C, and there was a tendency that the fire area enlarged from north to south. The research result provided reference for drilling detection and plugging and so on. [ABSTRACT FROM AUTHOR]

To develop low consumption and an environmentally friendly degradation technology for organic pollutants, micro-SiC/graphene composite materials were synthesized by photocatalytic reduction, and the composition and morphology of the prepared materials were characterized by XRD, FTIR, Raman spectroscopy, XPS, and SEM. Rhodamine B (RhB) was selected as the simulated pollutant to investigate the photocatalytic activity and stability of composite materials under visible light irradiation. The degradation mechanism was preliminarily discussed by active species capture experiments. Results show that the lives of photogenerated electron and photogenerated hole of SiC were prolonged when combined with graphene, which improved the photocatalytic activity and stability of composite materials. The degradation efficiency of RhB reached 92.7% with the composite material of SiC/graphene ratio (1:0.8) under 60 min irradiation, and the degradation process accorded with the first-order reaction kinetic equation. The contribution of main active species for photocatalytic degradation followed with a decreasing order of photogenerated hole (h + ), superoxide anion radical (·O 2 - ), photogenerated electron (e - ), and hydroxyl radical (·OH).

Objective: To evaluate the transmission risk and features of schistosomiasis by analyzing the data concerning positive rates of anti-schistosome antibody using catalytic models., Methods: Cross-sectional survey was conducted in seven villages with different endemicity of schistosomiasis in Jiangxi (Caohui, Xinhua, Jingtou villages), Anhui (Yuye, Tieguai, Longshang villages) and Hubei (Hebei village) Provinces in 2008. Serum samples were collected and indirect hemagglutination assay was performed to detect anti-schistosome antibodies in serum. Antibody positive rate was calculated and differences among villages and age groups as well as between genders were analyzed. Data of antibody positive rate based on age strata for each village were analyzed by two-stage catalytic model and reversible and two-stage compound catalytic model. Parameters of each model were estimated through the maximum likelihood method. Seroconversion rate and sero-negative conversion rate were estimated in the two-stage catalytic model. Seroconversion rate, seroreversion rate and sero-negative conversion rate were estimated in reversible and two-stage compound catalytic model. The fitting effect was evaluated through correlation analysis and chi-square tests. The best fitted models and parameters were used to analyze the transmission risk and characteristics of schistosomiasis., Results: A total of 6 428 individuals were examined with an average schistosomiasis antibody positive rate of 39.80%（2 485/6 428）. In terms of age, the peak of antibody positive rate in Caohui, Xinhua, Jingtou, Yuye, Tieguai, Longshang, and Hebei villages occurred in the age group of 46-50 （82.86%, 58/70）, 31-35 （60.78%, 31/51）, 31-35 （68.42%, 26/38）, 41-45（55.04%, 71/129）, 51-55 （62.38%, 63/101）, 56-60 （31.43%, 33/105）, and 16-20 （21.88%, 7/32） years old, respectively. In general, the antibody positive rate showed a trend of increase followed by a decrease with increasing age in each village. The best model for the data of Caohui, Xinhua and Jingtou and Yuye village was the two-stage catalytic model. The estimated seroconversion rate in these villages was 0.049 5, 0.044 0, 0.055 7, and 0.034 4 respectively, all higher than the corresponding sero-negative conversion rate of 0.005 9, 0.019 6, 0.015 5, and 0.017 8. The best model for the data of Longshang, Tieguai and Hebei villages was the reversible and two-stage compound model. The seroconversion rate in these villages was 0.062 9, 0.168 1, and 0.039 4 respectively, the seroreversion rate was 0.168 8, 0.121 1, and 0.152 2, and the sero-negative conversion rate was 0.001 7, 0.000 2, and 0.090 9., Conclusions: The catalytic model based on antibody positive rate by age strata could reflect the transmission rate and risk quantitatively and may provide guidance for making control strategies.

Objective: To analyze the progress of implementation of integrated strategy with emphasis on the control of infectious sources and effectiveness for joint-project of schistosomiasis control in Hubei province., Methods: Data on the endemic status and implementation of each integrated intervention in 6 collaborated counties including Gongan, Hanchuan, Honghu, Jiangling, Xiantao and Yangxin during 2009-2013 were collected and analyzed. 18 administrative villages with a history of endemic schistosomisis from 6 counties were selected for field survey. Individuals aged 6-65 years received screening test by IHA, and feces of antibody positive inhabitants were collected and tested by miracidia hatching technique. Hatching technique was conducted to determine the infection rate of schistosomiasis in cattle if there was any cattle existed., Results: Various interventions were conducted with adaption to the local situation by the Departments of Agriculture, Water Conservancy, Forestry, and Health. The total number of cattle decreased from 75 388 at the beginning of 2009 to 1 805 at the end of 2013 in 6 counties with a reduction rate of 97.5%, while the prevalence in cattle reduced to 0-0.3% in 2013. Snail-infested areas were stable but areas with infected snails decreased significantly, and no infected snails were found in 2012-2013. Meanwhile, the infection rate of human beings on county level were less than 1%. No infected snails and cattle were found in 18 selected villages and the prevalence in inhabitants was in the range of 0-0.8%., Conclusion: Cooperation between provincial government and the Ministries of Health and Agruiculture accelerates the process to reach the criteria of transmission control of schistosomiasis in Hubei Province. However, sustainable effort in needed as the current endemic situation of schistosomiasis is stillunstable.

Objective: To understand the comprehensive capability of helminth detection among professionals at different level of parasitic disease control institutions and promote the overall strength of diagnosis., Methods: Four professionals from each parasitic diseases control institutions were selected as contestant (age < 45 and at least two contestant from county-level institution). The content of contest included making stool slides with Kato-Katz method (five slides in thirty minutes, a total score of 15 and 9 as passing score) and identification of eleven common helminth eggs with microscopy (ten slides, five minutes per slide, a total score of 60, 36 as passing score)., Results: The average score of making slides in 119 contestants from 30 provinces was 11.4, and 119 contestants passed accounted for 93.3%. The average score of film-reading was 22.0, and 20 contestants passed accounted for 16.8%. There were no statistically significant differences between the results in different gender, age (< or = 30, 31-40, > 40), job title (the junior, intermediate, and senior), institution level (provincial, municipal, and county level) (P > 0.05). By Kato-Katz slide-making and film-reading, the scores in contestants from provinces with schistosomiasis control task (12.1 +/- 1.7, 32.1 +/- 11.5, respectively) were better than contestants from other provinces (11.1 +/- 1.8, 18.1 +/- 10.5, respectively). The scores in contestants from western (18.4 +/- 11.4) were lower than those from eastern (25.2 +/- 12.4) and central (24.1 +/- 13.1) for film-reading., Conclusion: The overall capability of parasitic disease examination is unbalanced among regions, and evidently there is a need to strengthen the capacity of pathogen detection in the disease control programs.

Objective: To explore the effects and the molecular mechanism of puerariae radix flavones (PRF) on acute myeloid leukemia cell line Kasumi-1 cells in vitro., Methods: Kasumi-1 cells treated by PRF for 48 hours were observed with Wright's and Hoechst 33258 dying. The apoptotic cells were analyzed by flow cytometry with AnnexinV/PI staining. The expression levels of bcl-2, Bim and Caspase-3/-8/-9 protein were assayed by Western blot and the AML1-ETO fusion gene was detected by real-time polymerase chain reaction., Results: PRF could induce Kasumi-1 cells to apoptosis effectively. The proportion of apoptotic cells in 50, 200 and 500 µg/ml PRF treatment groups were (14.1 ± 0.8)%, (17.7 ± 1.3)% and (32.4 ± 1.4)%, respectively, and significantly higher than that of control \[(7.8 ± 0.7)%\]. The relative expression levels of the anti-apoptotic Bcl-2 protein were 0.85 ± 0.05, 0.62 ± 0.07 and 0.43 ± 0.05; the apoptotic Bim protein were 0.21 ± 0.06, 0.39 ± 0.04 and 0.75 ± 0.05; the caspase-3 and caspase-9 were 0.92 ± 0.04, 1.21 ± 0.07, 1.33 ± 0.04 and 0.35 ± 0.05, 0.53 ± 0.03, 0.69 ± 0.07, respectively. Compared to the blank control group, all these changes were significant (P < 0.01). Nevertheless, nearly no changes could be observed on the expression level of AML1-ETO fusion gene and caspase-8 protein., Conclusion: Apoptosis of Kasumi-1 cells induced by PRF might correlate to the down-regulation of Bcl-2 protein expression and the activation of caspase-3 and caspase-8 protein in the cells. It seemed that all these effects had no relationship with the AML1-ETO fusion gene.

Objective: To evaluate the molluscicidal effect of film on ditches in mountainous schistosomiasis endemic regions., Methods: A ditch with Oncomelania hupensis snails was selected as experimental field. The ditch was divided into 3 parts (groups): a niclosamide plus film covering group (film covering after spraying by wettable powder of 50% niclosamide ethanolamine salt upon 2 g/m2), a film covering group (film covering directly without niclosamide spraying), and a control group (no molluscicidal measures). The snail investigation was performed 7, 10, 40, 60 d and 90 d after film covering. The temperatures outside and inside film were determined twice a day during the experiment., Results: The temperature inside the film was significantly higher than that outside the film (t = 4.12, P < 0.01). Compared with the densities of living snails before the experiment, the densities of living snails decreased by 99. 01% and 67.71% seven days post-film in the niclosamide plus film covering group and film covering group respectively; 96.58% and 93.06% ten days post-film respectively; both 100% forty days post-film. The multi-factor regression model indicated that covering film with niclosamide applying, extending film covering time, and increasing cumulate temperature inside film could enhance the molluscicidal effect., Conclusions: The film covering has well molluscicidal effect. The molluscicidal effect of covering film with niclosamide is better than that of covering film alone in short time. However, the covering film alone also has good molluscicidal effect when increasing covering time.

Objective: To observe the toxicity of niclosamide with plastic film mulching to fish., Methods: A ditch with Oncomelania snails was selected as the study site, and it was divided into a control group and a molluscicide group. After the river closure, the molluscicidal group was sprayed with niclosamide with a dosage of 2 g/m2, and then covered with plastic film; no molluscicide measure was implemented in the control group. The toxicity of the molluscicide to carp fish in resting and flowing water environment was observed., Results: In flowing water, the death rates of carp fry of the molluscicidal and control groups showed no statistical difference 7 d after the film mulching (P = 0. 680), and no carp fry died in the 2 groups after plastic film taking off for 4 d. The death rates of carp fry between the 3 sites (with a distance of 50, 100 and 150 m from the molluscicidal group, respectively) and the control group had no statistical difference 7 d after film mulching (P = 0.955), and no dead fry was discovered 4 d after taking off the film. In downstream, for the death rates of carp fry, there was no difference between the molluscicidal group and the control group (P = 0.376). The death rates of snails before and after the molluscicidal experiment showed a significant difference (P < 0.01)., Conclusions: The technology of niclosamide molluscicide with plastic film mulching can not only improve the molluscicidal effect, but also avoid the toxicity to fish, which is suitable for special environment such as a fish pond.

Objective: To evaluate the effect of schistosomiasis control by forbidding livestock denaturing on marshland with Oncomelania snails and to analyse its influencing factors., Methods: The village of Aiguo, Xinhe, Huangjia, Fanrong, Fengfu and Caomen and its respective nearby marshland, i.e., Aiguoniu, Liulingwei, Huangjianiu, Da, Goulian, and Litouzui, in Jinxian county, Jiangxi province were selected as the pilot areas for implementing the measures of forbidding livestock denaturing on the marshlands with Oncomelania snails during the period of the year 2005 to 2007. A total of 300 residents in each village were randomly chosen for stool examination with the Kato-Katz technique every year. The snail survey was carried out in spring and autumn every year on the marshlands close to the villages with systemic sampling method. The marshlands with a height 16.5 m above the sea level in Futian was selected for snail survey and planting with sesame. The residents aged 20 - 50 years old in Fengfu and Aiguo villages were studied by using questionnaire on the compliance of forbidding livestock pasturing on marshlands with Oncomelania snails., Results: Before implementation of the measures, human infection rate with Schistosoma japonicum was 11.35% (90/793) in Aiguo, 4.00% (12/300) in Xinhe, 4.00% (6/150) in Huangjia, 8.00% (12/150) in Fanrong, 3.17% (4/126) in Fengfu and 6.64% (14/211) in Caomen. After implementation in 2008, human schistsome infection rate in the aforementioned 6 villages was declined to 0.18% (1/551), 0.00% (0/348), 0.00% (0/316), 2.27% (7/308), 1.17% (5/428) and 1.16% (5/430), respectively. Only in Fengfu village the decline of the human prevalence was not significant (χ(2) = 2.4, P = 0.12), while in the other 5 villages, human prevalence rate had been declined significantly (χ(2) = 126.77, P < 0.01; χ(2) = 16.31, P < 0.01; χ(2) = 18.79, P < 0.01; χ(2) = 10.39, P < 0.01; χ(2) = 14.17, P < 0.01, respectively). Infected snails were not found in 5 out of the 6 marshlands close to the villages. Three infected snails were founded in Da marshland because of poor environmental isolation. Before planting, the living snail density was 0.063/0.11 m(2) (34/540), and after planting, the living snail density was 0.0074/0.11 m(2) (4/538), a 88.25% reduction (Z = 12.47, P < 0.01) was recorded through economy crop planting at Futiandaan marshland in 2008. A total of 986 pieces of questionnaire were provided, and 968 valid ones were collected. The results of questionnaire indicate that compliance of forbidding livestock denaturing on marshland with Oncomelania snails in Aiguo and Fengfu villages was 84.38% (216/256) and 75.42% (537/712), respectively. Using logistic regression model, knowledge level on harmfulness of livestock denaturing on marshland with Oncomelania snails, willingness of culture with machine to substitute traditional cattle culture, and willingness of investment to marshland culture development are 3 varieties that affect residents' implementation of forbidding livestock denaturing on marshland with Oncomelania snails., Conclusion: The infected snail density and human schistosome infection rate were reduced on the marshlands of well environmental isolation after 2 - 3 years implementation of forbidding livestock denaturing on marshlands with Oncomelania snails. The key influencing factors of forbidding livestock denaturing on marshland with Oncomelania snails are knowledge level on harmfulness of livestock denaturing on the snail infested marshlands, the willingness of machine culture to substitute cattle culture, and the willingness of investment to marshland culture development.

Objective: To evaluate the practical value and the advantages of globe geographical positioning with wireless communication monitoring and supervision system in the field survey., Methods: Spots which were randomly sampled by the National Ministry of Health for the investigation were chosen in the endemic areas for schistosomiasis in Jiangsu, Jiangxi, Anhui, Hunan, Hubei, Sichuan and Yunnan provinces. Portable GPS CEC9680 was used for collecting relevant waypoints and track, recording on-the-spot geographical positions. The positioning data package was sent back synchronously in the form of short message of SMS to the monitoring service center, and the moving routes of the terminal receiver monitored were displayed on the GIS map to achieve real-time supervision and staff scheduling., Results: With globe geographical positioning with wireless communication monitoring and supervision system, accurate positioning of 12 spots in the provinces of Jiangsu and 3 trial spots for schistosomiasis control with comprehensive treatment designated by the State Council has been established with real-time communicating recording, and monitoring systems., Conclusion: The globe geographical positioning with wireless communication monitoring and supervision system has provided a technical platform for the survey of schistosomiasis and other infectious diseases.

Objective: To analyze factors affecting transmission of schistosomiasis japonica in Poyang Lake., Methods: Successive surveillance data for at least three years from 1992 to 1998 at the schistosomiasis endemic administrative villages surrounding Poyang Lake were collected, including the egg positive rate by stool examination, investment on treatment of patients and mollusciciding in snail habitat, risk areas, bovine infection rate. Data on rainfall and temperature were also obtained from the relevant agencies. Step-wised regression method was employed to analyze the data., Results: The regression model established is statistically significant, R2 equals 0.735, P < 0.01. The accepted variables affecting the transmission of the disease were natural logarithm of human infection rate in last year, risk areas, infection rate of bovine, investment values of niclosamide per risk area and value of praziquantel administered per infection rate., Conclusion: Chemotherapy and mollusciciding effectively reduced schistosomiasis transmission in Poyang lake region, while the infection rate, risk areas, bovine infection rate still drive the transmission.