The determination of gas pressure before uncovering coal in cross-cuts and in shafts is one of the important steps in pre- dicting coal and gas outbursts. However, the time spent for testing gas pressure is, at presen...The determination of gas pressure before uncovering coal in cross-cuts and in shafts is one of the important steps in pre- dicting coal and gas outbursts. However, the time spent for testing gas pressure is, at present, very long, seriously affecting the ap- plication of outburst prediction techniques in opening coal seams in cross-cuts and shafts. In order to reduce the time needed in gas pressure tests and to improve the accuracy of tests, we analyzed the process of gas pressure tests and examined the effect of the length of boreholes in coal seams in tests. The result shows that 1) the shorter the borehole, the easier the real pressure value of gas can be obtained and 2) the main factors affecting the time spent in gas pressure tests are the length of the borehole in coal seams, the gas emission time after the borehole has been formed and the quality of the borehole-sealing. The longer the length of the bore- hole, the longer the gas emission time and the larger the pressure-relief circle formed around the borehole, the longer the time needed for pressure tests. By controlling the length of the borehole in a test case in the Huainan mining area, and adopting a quick sealing technique using a sticky liquid method, the sealing quality was clearly improved and the gas emission time as well as the amount of gas discharged greatly decreased. Before the method described, the time required for the gas pressure to increase during the pressure test process, was more than 10 days. With our new method the required time is only 5 hours. In addition, the accuracy of the gas pressure test is greatly improved.展开更多
Objective This study aimed to analyze the mechanism of action of the Pingyang Jiangya Formula(平阳降压方,PYJYF)in treating hypertension,based on network pharmacology,and to verify the subsequent predictions through an...Objective This study aimed to analyze the mechanism of action of the Pingyang Jiangya Formula(平阳降压方,PYJYF)in treating hypertension,based on network pharmacology,and to verify the subsequent predictions through animal experiments.Methods The active components and related target genes of PYJYF were screened using the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform(TCMSP),Bioinformatics Analysis Tool for Molecular Mechanism of Traditional Chinese Medicine(BATMAN-TCM),Encyclopedia of Traditional Chinese Medicine(ETCM),and Drug Bank databases and available literature.The hypertension target genes were screened based on Therapeutic Target Database(TTD),GeneCards,Online Mendelian Inheritance in Man(OMIM),UniProt,and relevant literature.The component-disease-target network intersection target genes were inputted into the STRING database,and the key target genes were selected according to the degree algorithm.Gene Ontology(GO)analysis and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analyses were performed to explore the multitarget mechanism of action and molecular regulatory network of PYJYF in the treatment of hypertension.To verify this prediction,we used PYJYF to intervene in spontaneously hypertensive rats(SHRs)and Wistar–Kyoto rats(WKY)as normal control,and the noninvasive tail artery manometry method was used to measure systolic blood pressure(SBP)in the rat tail before PYJYF intervention.After drug intervention,the SBP of each group rats were measured and compared every week.Enzyme-linked immunosorbent assay(ELISA)was used to test plasma renin,angiotensin II(Ang II),and aldosterone(Ald)levels,and hematoxylin-eosin(HE)staining was used to observe pathological damage to the renal vessels in each group of rats.Western blot and reverse transcription real-time quantitative PCR(RT-PCR)were used to detect the protein and mRNA expression levels of PI3 K,AKT1,BAX,and Bcl-2,respectively.Results A total of 4123 hypertension targets were obtained from related databases.From the TCMSP and chemical databases,78 active components of PYJYF and the corresponding 401 drug targets were retrieved.Data analysis revealed that 208 drug targets directly interacted with the hypertension targets in PYJYF.The 10 targets most closely related to hypertension target proteins in PYJYF were directly retrieved from relevant databases.GO analysis revealed that 10 direct target proteins were involved in all aspects of the antihypertensive effects of PYJYF,as well as molecular biological processes,such as the regulation of blood pressure,renin-angiotensin-aldosterone system(RAAS),angiotensin-mediated ligand reactions,and biological stimulation of cardiomyocyte apoptosis.KEGG pathway enrichment analysis revealed that PYJYF directly affected 20 signaling pathways associated with hypertension.In animal experiments,PYJYF reduced the protein and m RNA levels of PI3 K,Akt,and Bax and upregulated the expression of the protein and m RNA levels of Bcl-2,reduced plasma renin,Ang II,and Ald levels,improved the hyperactivity of RAAS,and significantly reduced SBP in SHRs.Conclusion PYJYF is effective for hypertension therapy that acts through multiple compounds and targets.The possible underlying molecular mechanism includes regulating the PI3 K/Akt signaling pathway to suppress RAAS,increasing the ratio of Bcl-2/Bax proteins,and inhibiting apoptosis,thereby mediating the repair of renal and renal vascular damage caused by hypertension.These findings warrant further research for use in clinical settings.展开更多
To better understand the process of precipitation and water cycle, the composition of stable isotope in precipitation and its influences by different vapor sources in the eastern of Qilian Mountains were conducted fro...To better understand the process of precipitation and water cycle, the composition of stable isotope in precipitation and its influences by different vapor sources in the eastern of Qilian Mountains were conducted from June 2013 to May 2014. The total of 100 precipitation samples were collected in Wushaoling national meteorological station located in the eastern of Qilian Mountains. The analysis indicates that the slope of Local Meteoric Water Line is lower than that of Global Meteoric Water Line. The average values of δ18 O and δD in precipitation are higher in summer but lower in winter. Except for negative correlation with relative humidity, the stable isotope values in precipitation are positive correlations with temperature, precipitation and water vapor pressure. Influenced by water vapor source, the values of d-excess are lower for the Westerly wind and the South Asia Monsoon onJuly and the Westerly wind and the East Asia Monsoon on August, but they are higher for the Westerly wind on other months, that they are also influenced by the weather conditions in rainfall process. The variation of stable isotope in precipitation exhibited significant temperature effect, and there is also some precipitation amount effect in spring and summer.展开更多
A method for improving the level of reliability of distribution systems is presented by employing an integrated voltage sag mitigation method that comprises a two-staged strategy,namely,distribution network reconfigur...A method for improving the level of reliability of distribution systems is presented by employing an integrated voltage sag mitigation method that comprises a two-staged strategy,namely,distribution network reconfiguration(DNR)followed by DSTATCOM placement.Initially,an optimal DNR is applied to reduce the propagated voltage sags during the test period.The second stage involves optimal placement of the DSTATCOM to assist the already reconfigured network.The gravitational search algorithm is used in the process of optimal DNR and in placing DSTATCOM.Reliability assessment is performed using the well-known indices.The simulation results show that the proposed method is efficient and feasible for improving the level of system reliability.展开更多
A model for gas–liquid annular and stratified flow through a horizontal pipe is investigated, using the two-phase hydrokinetics theory. Taking into consideration the flow factors including the void fraction, the fric...A model for gas–liquid annular and stratified flow through a horizontal pipe is investigated, using the two-phase hydrokinetics theory. Taking into consideration the flow factors including the void fraction, the friction between the two phases and the entrainment in the gas core, the one-dimensional momentum equation for gas has been solved. The differential pressure of the wet gas between the two tapings in the straight pipe has been modeled in the pressure range of 0.1–0.8 MPa. In addition a more objective iteration approach to determine the local void fraction is proposed. Compared with the experimental data, more than 83% deviation of the test data distributed evenly within the band of ± 10%. Since the model is less dependent on the specific empirical apparatus and data,it forms the foundation for further establishing a flow measurement model of wet gas which will produce fewer biases in results when it is extrapolated.展开更多
The flowing mechanism of a low permeability gas reservoir is different from a conventional gas reservoir,especially for that with higher irreducible water saturation the threshold pressure gradient exists. At present,...The flowing mechanism of a low permeability gas reservoir is different from a conventional gas reservoir,especially for that with higher irreducible water saturation the threshold pressure gradient exists. At present,in all the deliverability equation,the additional pressure drop caused by the threshold pressure gradient is viewed as constant,but this method has big error in the practical application. Based on the non-Darcy steady flow equation,the limited integral of the additional pressure drop is solved in this paper and it is realized that the additional pressure drop is not a constant but has something to do with production data,and a new deliverability equation is derived,with the relevant processing method for modified isochronal test data. The new deliverability equation turns out to be practical through onsite application.展开更多
We intend to realize the step-up and step-down operators of the potential V (x) = V1 e 2βx+V2 e βx. It is found that these operators satisfy the commutation relations for the SU(2) group. We find the eigenfunctions ...We intend to realize the step-up and step-down operators of the potential V (x) = V1 e 2βx+V2 e βx. It is found that these operators satisfy the commutation relations for the SU(2) group. We find the eigenfunctions and the eigenvalues of the potential by using the Laplace transform approach to study the Lie algebra satisfied the ladder operators of the potential under consideration. Our results are similar to the ones obtained for the Morse potential (β→β).展开更多
基金supported by the National Basic Research Program of China (No.2006CB202204-3).
文摘The determination of gas pressure before uncovering coal in cross-cuts and in shafts is one of the important steps in pre- dicting coal and gas outbursts. However, the time spent for testing gas pressure is, at present, very long, seriously affecting the ap- plication of outburst prediction techniques in opening coal seams in cross-cuts and shafts. In order to reduce the time needed in gas pressure tests and to improve the accuracy of tests, we analyzed the process of gas pressure tests and examined the effect of the length of boreholes in coal seams in tests. The result shows that 1) the shorter the borehole, the easier the real pressure value of gas can be obtained and 2) the main factors affecting the time spent in gas pressure tests are the length of the borehole in coal seams, the gas emission time after the borehole has been formed and the quality of the borehole-sealing. The longer the length of the bore- hole, the longer the gas emission time and the larger the pressure-relief circle formed around the borehole, the longer the time needed for pressure tests. By controlling the length of the borehole in a test case in the Huainan mining area, and adopting a quick sealing technique using a sticky liquid method, the sealing quality was clearly improved and the gas emission time as well as the amount of gas discharged greatly decreased. Before the method described, the time required for the gas pressure to increase during the pressure test process, was more than 10 days. With our new method the required time is only 5 hours. In addition, the accuracy of the gas pressure test is greatly improved.
基金funding support from the National Natural Science Foundation of China(No.81874464)National Major New Drug Development Project(No.2019ZX09301-103)Provincial Department of Graduate Research Innovation Project of Hunan(No.CX20190565)。
文摘Objective This study aimed to analyze the mechanism of action of the Pingyang Jiangya Formula(平阳降压方,PYJYF)in treating hypertension,based on network pharmacology,and to verify the subsequent predictions through animal experiments.Methods The active components and related target genes of PYJYF were screened using the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform(TCMSP),Bioinformatics Analysis Tool for Molecular Mechanism of Traditional Chinese Medicine(BATMAN-TCM),Encyclopedia of Traditional Chinese Medicine(ETCM),and Drug Bank databases and available literature.The hypertension target genes were screened based on Therapeutic Target Database(TTD),GeneCards,Online Mendelian Inheritance in Man(OMIM),UniProt,and relevant literature.The component-disease-target network intersection target genes were inputted into the STRING database,and the key target genes were selected according to the degree algorithm.Gene Ontology(GO)analysis and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analyses were performed to explore the multitarget mechanism of action and molecular regulatory network of PYJYF in the treatment of hypertension.To verify this prediction,we used PYJYF to intervene in spontaneously hypertensive rats(SHRs)and Wistar–Kyoto rats(WKY)as normal control,and the noninvasive tail artery manometry method was used to measure systolic blood pressure(SBP)in the rat tail before PYJYF intervention.After drug intervention,the SBP of each group rats were measured and compared every week.Enzyme-linked immunosorbent assay(ELISA)was used to test plasma renin,angiotensin II(Ang II),and aldosterone(Ald)levels,and hematoxylin-eosin(HE)staining was used to observe pathological damage to the renal vessels in each group of rats.Western blot and reverse transcription real-time quantitative PCR(RT-PCR)were used to detect the protein and mRNA expression levels of PI3 K,AKT1,BAX,and Bcl-2,respectively.Results A total of 4123 hypertension targets were obtained from related databases.From the TCMSP and chemical databases,78 active components of PYJYF and the corresponding 401 drug targets were retrieved.Data analysis revealed that 208 drug targets directly interacted with the hypertension targets in PYJYF.The 10 targets most closely related to hypertension target proteins in PYJYF were directly retrieved from relevant databases.GO analysis revealed that 10 direct target proteins were involved in all aspects of the antihypertensive effects of PYJYF,as well as molecular biological processes,such as the regulation of blood pressure,renin-angiotensin-aldosterone system(RAAS),angiotensin-mediated ligand reactions,and biological stimulation of cardiomyocyte apoptosis.KEGG pathway enrichment analysis revealed that PYJYF directly affected 20 signaling pathways associated with hypertension.In animal experiments,PYJYF reduced the protein and m RNA levels of PI3 K,Akt,and Bax and upregulated the expression of the protein and m RNA levels of Bcl-2,reduced plasma renin,Ang II,and Ald levels,improved the hyperactivity of RAAS,and significantly reduced SBP in SHRs.Conclusion PYJYF is effective for hypertension therapy that acts through multiple compounds and targets.The possible underlying molecular mechanism includes regulating the PI3 K/Akt signaling pathway to suppress RAAS,increasing the ratio of Bcl-2/Bax proteins,and inhibiting apoptosis,thereby mediating the repair of renal and renal vascular damage caused by hypertension.These findings warrant further research for use in clinical settings.
基金funded by the Youth Innovation Promotion Association,CAS(2013274)National Nature Science Foundation of China(91547102 and 41661005)+2 种基金Gansu Province Science Fund for Distinguished Young Scholars(1506RJDA282)National Key R&D Program of China(2017YFC0404305)National Natural Science Foundation Innovation Research Group Science Foundation of China(41421061)
文摘To better understand the process of precipitation and water cycle, the composition of stable isotope in precipitation and its influences by different vapor sources in the eastern of Qilian Mountains were conducted from June 2013 to May 2014. The total of 100 precipitation samples were collected in Wushaoling national meteorological station located in the eastern of Qilian Mountains. The analysis indicates that the slope of Local Meteoric Water Line is lower than that of Global Meteoric Water Line. The average values of δ18 O and δD in precipitation are higher in summer but lower in winter. Except for negative correlation with relative humidity, the stable isotope values in precipitation are positive correlations with temperature, precipitation and water vapor pressure. Influenced by water vapor source, the values of d-excess are lower for the Westerly wind and the South Asia Monsoon onJuly and the Westerly wind and the East Asia Monsoon on August, but they are higher for the Westerly wind on other months, that they are also influenced by the weather conditions in rainfall process. The variation of stable isotope in precipitation exhibited significant temperature effect, and there is also some precipitation amount effect in spring and summer.
基金Project(DIP-2012-30)supported by the Universiti Kebangsaan,Malaysia
文摘A method for improving the level of reliability of distribution systems is presented by employing an integrated voltage sag mitigation method that comprises a two-staged strategy,namely,distribution network reconfiguration(DNR)followed by DSTATCOM placement.Initially,an optimal DNR is applied to reduce the propagated voltage sags during the test period.The second stage involves optimal placement of the DSTATCOM to assist the already reconfigured network.The gravitational search algorithm is used in the process of optimal DNR and in placing DSTATCOM.Reliability assessment is performed using the well-known indices.The simulation results show that the proposed method is efficient and feasible for improving the level of system reliability.
基金Supported by the National Nature Science Foundation of China(61603207 and61571252)Tsinghua University Shenzhen Graduate School Grant(050100001)
文摘A model for gas–liquid annular and stratified flow through a horizontal pipe is investigated, using the two-phase hydrokinetics theory. Taking into consideration the flow factors including the void fraction, the friction between the two phases and the entrainment in the gas core, the one-dimensional momentum equation for gas has been solved. The differential pressure of the wet gas between the two tapings in the straight pipe has been modeled in the pressure range of 0.1–0.8 MPa. In addition a more objective iteration approach to determine the local void fraction is proposed. Compared with the experimental data, more than 83% deviation of the test data distributed evenly within the band of ± 10%. Since the model is less dependent on the specific empirical apparatus and data,it forms the foundation for further establishing a flow measurement model of wet gas which will produce fewer biases in results when it is extrapolated.
基金National Basic Research Program of China(2007CB209506)
文摘The flowing mechanism of a low permeability gas reservoir is different from a conventional gas reservoir,especially for that with higher irreducible water saturation the threshold pressure gradient exists. At present,in all the deliverability equation,the additional pressure drop caused by the threshold pressure gradient is viewed as constant,but this method has big error in the practical application. Based on the non-Darcy steady flow equation,the limited integral of the additional pressure drop is solved in this paper and it is realized that the additional pressure drop is not a constant but has something to do with production data,and a new deliverability equation is derived,with the relevant processing method for modified isochronal test data. The new deliverability equation turns out to be practical through onsite application.
基金supported by the Scientific and Technical Research Council of Turkey
文摘We intend to realize the step-up and step-down operators of the potential V (x) = V1 e 2βx+V2 e βx. It is found that these operators satisfy the commutation relations for the SU(2) group. We find the eigenfunctions and the eigenvalues of the potential by using the Laplace transform approach to study the Lie algebra satisfied the ladder operators of the potential under consideration. Our results are similar to the ones obtained for the Morse potential (β→β).
