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Conversion regular patterns of acetic acid,propionic acid and butyric acid in UASB reactor 被引量:6
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作者 LIUMin RENNan-qi +2 位作者 CHENYing ZHUWen-fang DINGJie 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第3期387-391,共5页
On the basis of continuous tests and batch tests, conversion regular patterns of acetate, propionate and butyrate in activated sludge at different heights of the UASB reactor were conducted. Results indicated that the... On the basis of continuous tests and batch tests, conversion regular patterns of acetate, propionate and butyrate in activated sludge at different heights of the UASB reactor were conducted. Results indicated that the conversion capacity of the microbe is decided by the substrate characteristic when sole VFA is used as the only substrate. But when mixed substrates are used,the conversion regulations would have changed accordingly. Relationships of different substrates vary according to their locations. In the whole reactor, propionate's conversion is restrained by acetate and butyrate of high concentration. On the top and at the bottom of the reactor, conversion of acetate, but butyrate, is restrained by propionate. And in the midst, acetate's conversion is accelerated by propionate while that of butyrate is restrained. It is proved, based on the analysis of specific conversion rate, that the space distribution of the microbe is the main factor that affects substrates' conversion. The ethanol type fermentation of the acidogenic phase is the optimal acid type fermentation for the two phase anaerobic process. 展开更多
关键词 conversion regular pattern VFAs specific conversion rate UASB reactor
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Control of In Vitro Regeneration of Individual Reproductive and Vegetative Organs in Dracaena fragrans cv. massangeana Hort. Regularities of the Direct Regenerationof Individual Organs In Vitro 被引量:1
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作者 陆文樑 《Acta Botanica Sinica》 CSCD 2003年第12期1453-1464,共12页
Various individual organs (tepal, flower bud, inflorescence branch, inflorescence, adult vegetative bud and juvenile vegetative bud) were directly regenerated respectively by callus in Dracaena fragrans cv. massangean... Various individual organs (tepal, flower bud, inflorescence branch, inflorescence, adult vegetative bud and juvenile vegetative bud) were directly regenerated respectively by callus in Dracaena fragrans cv. massangeana Hort. During the regeneration of these individual organs some regularity phenomena were observed. Firstly, the kind range of the individual organs, which are directly regenerated in vitro, is in close relationship to the differentiated stages of the organs used for explant excision during plant ontogeny. The explants excised from the epigeous organ that is differentiated at some stage (stage A) during plant ontogeny must be able to separately regenerate all of those individual epigeous organs: ones differentiated slightly later than the stage A, ones differentiated at the stage A and all ones differentiated earlier than the stage A. Secondly, within this range which kind of organ is regenerated depends on the exogenous auxin concentrations in medium. With the gradual increase of 2,4-D concentration from 0.005 mg/L to 0.5 mg/L, the kinds of regenerated organs will change by the order as follows: vegetative bud, inflorescence, inflorescence branch, flower bud, tepal. These regularities will be able to be used for inducing the direct regeneration of a given epigeous organ in angiosperms. 展开更多
关键词 direct regeneration of a given organ regular patterns for the direct regeneration of individual organs reversed development of cells in vitro cell totipotency expression Dracaena fragrans
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Study on the pattern of train arrival headway time in high-speed railway
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作者 Changhai Tian Shoushuai Zhang 《Railway Sciences》 2024年第3期344-366,共23页
Purpose-The design goal for the tracking interval of high-speed railway trains in China is 3 min,but it is difficult to achieve,and it is widely believed that it is mainly limited by the tracking interval of train arr... Purpose-The design goal for the tracking interval of high-speed railway trains in China is 3 min,but it is difficult to achieve,and it is widely believed that it is mainly limited by the tracking interval of train arrivals.If the train arrival tracking interval can be compressed,it will be beneficial for China's high-speed railway to achieve a 3-min train tracking interval.The goal of this article is to study how to compress the train arrival tracking interval.Design/methodologylapproach-By simulating the process of dense train groups arriving at the station and stopping,the headway between train arrivals at the station was calculated,and the pattern of train arrival headway was obtained,changing the traditional understanding that the train arrival headway is considered the main factor limiting the headway of trains.Findings-When the running speed of trains is high,the headway between trains is short,the length of the station approach throat area is considerable and frequent train arrivals at the station,the arrival headway for the first group or several groups of trains will exceed the headway,but the subsequent sets of trains will havea headway equal to the arrival headway.This convergence characteristic is obtained by appropriately increasing the running time.Originality/value-According to this pattern,there is no need to overly emphasize the impact of train arrival headway on the headway.This plays an important role in compressing train headway and improving high-speedrailwaycapacity. 展开更多
关键词 High speed railway Train headway Train arrival headway regular pattern Paper type Research paper
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Quantitative studies of the regular distribution pattern for Salmonella enteritidis in the internal organs of mice after oral challenge by a specific real-time polymerase chain reaction 被引量:7
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作者 Shu-Xuan Deng An-Chun Cheng +5 位作者 Ming-Shu Wang Ping Cao Bin Yan Nian-Chun Yin Sheng-Yan Cao Zhen-Hua Zhang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第5期782-789,共8页
AIM: To identify and understand the regular distribution pattern for Salmonella enteritidis (S. enteritidis) in the internal organs of mice after an oral challenge over a 3 wk period. METHODS: Assays based on the ... AIM: To identify and understand the regular distribution pattern for Salmonella enteritidis (S. enteritidis) in the internal organs of mice after an oral challenge over a 3 wk period. METHODS: Assays based on the serovar-specific DNA sequence of S. enteritidis from GenBank, and a serovar-specific real-time, fluorescence-based quantitative polymerase chain reaction (FQ-PCR) were developed for the detection of S. enteritidis. We used this assay to detect genomic DNA of S. enteritidis in the blood and the internal organs, including heart, liver, spleen, kidney, pancreas, and gallbladder, from mice after oral challenge at different time points respectively.RESULTS: The results showed that the spleen was positive at 12 h post inoculation (PI), and the blood was at 14 h PI. The organism was detected in the liver and heart at 16 h PI, the pancreas was positive at 20 h PI, and the final organs to show positive results were the kidney and gallbladder at 22 h PI. The copy number of S. enteritidis DNA in each tissue reached a peak at 24-36 h PI, with the liver and spleen containing high concentrations of S. enteritidis, whereas the blood, heart, kidney, pancreas, and gallbladder had low concentrations. S. enteritidis populations began to decrease and were not detectable at 3 d PI, but were still present up to 12 d PI in the gallbladder, 2 wk for the liver, and 3 wk for the spleen without causing apparent symptoms.CONCLUSION: The results provided significant data for understanding the life cycle of S. enteritidis in the internal organs, and showed that the liver and spleen may be the primary sites for setting itself up as a commensa over a long time after oral challenge. Interestingly, it may be the first time reported that the gallbladder is a site of carriage for S. enteritidis over a 12 d period. This study will help to understand the mechanisms of action of S. enteriCdis infection in vivo. 展开更多
关键词 Fluorescence-based quantitative polymerase chain reaction Internal organs Salmonella enteritidis regular distribution pattern
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Spatial Pressure Distribution of Cultivated Land and the Analysis of Food Safety in Kunming City,China
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作者 PENG Er-rui WANG Sui +3 位作者 LV Xia ZHANG Jian-sheng ZHANG Chuan HAO Li-sha 《Asian Agricultural Research》 2010年第2期53-56,共4页
The social and economical condition,cultivated land resources and general situation of grain production of research area are introduced.According to relevant data of cultivated land of Kunming City in 2006,taking the ... The social and economical condition,cultivated land resources and general situation of grain production of research area are introduced.According to relevant data of cultivated land of Kunming City in 2006,taking the minimum per capita cultivated land and index model of cultivated land pressure,and combining with two conditions of per capita grain demand which are 300 kg and 400 kg,the comparative research method was used to calculate and analyze the minimum per capita cultivated land and index model of cultivated land pressure.The results show that when per capita grain demand-Gr is 300 kg,the per capita cultivated land in Kunming City has regional differences,reflects different regular patterns of spatial distribution,and presents obvious and typical radial distribution.Urban area of Kunming has the lowest point and be taken as the center,per capita cultivated land decreases progressively from suburban to the periphery;when per capita grain demand-Gr is 400 kg,under the same consumption level,cultivated land pressures of each county in Kunming City are different,and so are the driven factors;when per capita grain demand-Gr is 300 kg or 400 kg,the indexes of cultivated land pressure in Kunming are all greater than 1,cultivated land pressure is enormous,the indexes of cultivated land pressure of each county(district) have two conditions-greater than 1 and less than 2,and the reasons differ from one another.Combining with the spatial distribution characteristics of the cultivated land and food and the situation of industrial development,the countermeasures and suggestions are put forwarded to make full use of back-up cultivated land,to plan the distribution of industrial structure in each county(district) of Kunming City as a whole,to dispose cultivated land resources reasonably and so on. 展开更多
关键词 Food safety Index model of cultivated land pressure Minimum per capita cultivated land regular pattern of spatial distribution China
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A Comparative Study of The Regular Pattern of Syndrome and Treatment of Lung-intestine Related Diseases in Ancient and Modern Medical Cases Based on Data Mining 被引量:1
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作者 Fang-Fang Mo Le-Peng Wang Si-Hua Gao 《World Journal of Traditional Chinese Medicine》 2016年第1期62-67,共6页
Objective: To analyze the similarities and differences of the applications of "the lung and large intestine being interior-exteriorly related"between the ancient and modern clinical practices, and to reveal ... Objective: To analyze the similarities and differences of the applications of "the lung and large intestine being interior-exteriorly related"between the ancient and modern clinical practices, and to reveal the theory meaning.Method: Based on the ancient and modern medical cases database, 245 ancient medical records and 373 modern medical records were studied with the general statistical description and analysis of association rules, and the results were compared to summarize the similarities and differences of the regular pattern of syndrome and treatment on lung-large intestine related diseases in ancient and modern medical records.Results: In modern medical cases, intestinal diseases appeared with the main symptom of constipation due to deficiency of lung qi and qi stagnation of large intestine were always treated by purgation together with replenishing and restoring lung qi. In ancient medical cases, large intestine heat was always caused by lung heat and a variety of diarrhea symptoms appeared. They were always treated by clearing heat and moistening lungs. In addition, the symptom of bound stool caused by qi stagnation of large intestine due to lung qi stagnation was always treated by lowering lung qi to regulate and smooth large intestine qi. And Armeniae Amarum Semen was used by both as a core medicinal herb.Conclusion: Ascending-descending of qi movement is the core of the lung and large intestine relationship. In other words, the lung and the large intestine communicate through qi. 展开更多
关键词 Medical cases The lung and large intestine being interior-exteriorly related Lung-large intestine related diseases The regular pattern of syndrome and treatment Comparative study
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The essential aspect and regular pattern of ion transfer across the liquid-liquid interface
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作者 WANG,Er-Kang SUN,Zhi-Sheng Changchun Institute of Applied Chemistry,Chinese Academy of Sciences,Changchun 130022 《Chinese Journal of Chemistry》 SCIE CAS CSCD 1990年第3期228-238,共2页
Three empirical rules of interfacial potential and Gibb's energy with the radius,charge number of transfer ions and dielectric constant of organic phase are obtained for the ion transfer across the liquid-liquid i... Three empirical rules of interfacial potential and Gibb's energy with the radius,charge number of transfer ions and dielectric constant of organic phase are obtained for the ion transfer across the liquid-liquid interface,which are verified by the transfer of simple anions,dye ions and metal ions facilitated by neutral ionophores across the interface between water and some organic solvents, and deduced theoretically based on the electrostatic interaction of ion and high-permittivity solvent. The rules are proved to be effective of choosing supporting electrolytes and searching for new transfer system which follows the rule that r/n of transfer ion should be larger than that of electrolytes ion in water phase and less than that in organic phase.A rule for judgement of the charge sign of transfer ion is suggested firstly based on the relationship between interfacial half-wave potential and dielectric constant of organic phase. 展开更多
关键词 The essential aspect and regular pattern of ion transfer across the liquid-liquid interface
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Design of hexagon microstrip antenna for vehicle-to-vehicle communication 被引量:4
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作者 Hao Honggang Li Jiayu +1 位作者 Huang Daili Luo Wei 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2016年第4期69-76,共8页
Considering the shortcomings of the existing vehicle-to-vehicle(V2V) communication antennas, this paper proposes a regular hexagon broadband microstrip antenna. By loading shorting pins and etching V-shape slots wit... Considering the shortcomings of the existing vehicle-to-vehicle(V2V) communication antennas, this paper proposes a regular hexagon broadband microstrip antenna. By loading shorting pins and etching V-shape slots with different size at each angle of the regular hexagon patch, it realizes impedance matching and obtains better impedance bandwidth. The simulated results show that the relative bandwidth of this antenna reaches 35.55%, covers the frequency band of 4.74 GHz to 6.79 GHz. The antenna acquires an omni-directional radiation pattern in the horizontal plane whose out of roundness is less than 0.5 d B. In addition, the antenna is manufactured and tested, whose tested results are basically consistent with simulated results. Because the height of antenna is 3 mm, it is easy to be hidden on roof of a vehicle for V2 V communication. 展开更多
关键词 regular hexagon microstrip antenna shorting pins V-shape slots omni-directional radiation pattern V2V communication
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