An overview on nonlinear porous flow in low permeability porous media

This paper gives an overview on nonlinear porous flow in low permeability porous media, reveals the microscopic mechanisms of flows, and clarifies properties of porous flow fluids. It shows that, deviating from Darcy＇s linear law, the porous flow characteristics obey a nonlinear law in a low-permeability porous medium, and the viscosity of the porous flow fluid and the permeability values of water and oil are not constants. Based on these characters, a new porous flow model, which can better describe low permeability reservoir~ is established. This model can describe various patterns of porous flow, as Darcy＇s linear law does. All the parameters involved in the model, having definite physical meanings, can be obtained directly from the experiments.

On the Development of an Effective Pressure Driving System for Ultra-Low Permeability Reservoirs

Given its relevance to the exploitation of ultra-low permeability reservoirs,which account for a substantial proportion of the world’s exploited and still unexploited reserves,in the present study the development of an adequate water injection system is considered.Due to the poor properties and weak seepage capacity of these reservoirs,the water injection pressure typically increases continuously during water flooding.In this research,the impact on such a process of factors as permeability,row spacing,and pressure gradient is evaluated experimentally using a high-pressure large-scale outcrop model.On this basis,a comprehensive evaluation coefficient is introduced able to account for the effective driving pressure.

Evaluation of Wild Paeonia veitchii Lynch from Sichuan Based on Moisture, Ash and Extract Contents

[Objectives]The research aimed to determine the contents of moisture,ash and extract of wild Paeonia veitchii Lynch produced in Sichuan,so as to provide the basis for evaluating quality of wild P.veitchii Lynch from Sichuan.[Methods]Moisture,ash and extract contents of wild P.veitchii Lynch were respectively determined according to the fourth part of the Chinese Pharmacopoeia of 2015 version,and correlation analysis and TOPSIS analysis were used for data processing.[Results]12 batches of samples all corresponded with the provision that moisture of P.veitchii Lynch should not exceed 14.0%in the Standard of Traditional Chinese Medicine in Sichuan Province of 2010 version;11 batches of samples all corresponded with the provisions that total ash and acid insoluble ash of P.veitchii Lynch should not exceed 7.0%and 1.0%in the Standard of Traditional Chinese Medicine in Sichuan Province of 2010 version;average content of alcohol-soluble extract by hot dipping from 12 batches of samples was 42.29%,which was not less than 30.0%.In P.veitchii Lynch,moisture and acid insoluble ash showed positive correlation with altitude,while total ash and extract content were negatively correlated with altitude.Taking moisture,ash and extract as evaluation indexes,No.9 P.veitchii Lynch sample was the best.[Conclusions]Moisture and ash of P.veitchii Lynch corresponded with the provisions of the Chinese Pharmacopoeia of 2015 version and the Standard of Traditional Chinese Medicine in Sichuan Province of 2010 version,while extract content was higher than provision of the standard.The research could provide reference basis for rational utilization and quality evaluation of P.veitchii Lynch resources.

Quality Evaluation of Yi Medicine "Qibujing" Based on Determination of Water Content and Ash Content

[Objectives]To determine the water content,total ash content and acid-insoluble ash content of Yi medicinal material"Qibujing",so as to provide experimental basis for establishing the Quality Standard(Draft)of Yi Medicinal Material"Qibujing"in Sichuan Province.[Methods]According to the second method(drying method)in 0832 water content determination method and 2301 ash content determination method in Chinese Pharmacopoeia(2015 Edition),it was determined,respectively,and the data were processed by IBM SPSS Statistics 26 and DPS 7.05 data processing system.[Results]All the 14 batches of sample met the stipulation that the water content should not exceed 12.0%,the total ash content should not exceed 8.0%,and the acid-insoluble ash content should not exceed 1.5%under"Guan Zhong-(Qibujing)"in the 2005 edition of Yunnan Traditional Chinese Medicine Standard.There was a negative correlation between water content,acid-insoluble ash content and altitude,and a positive correlation between total ash content and altitude.[Conclusions]It is suggested that Quality Standard(Draft)of Yi Medicinal Material"Qibujing"in Sichuan Province stipulate that the water content should not exceed 12.0%,the total ash content should not exceed 8.0%,and the acid-insoluble ash content should not exceed 1.5%.

Study on the Identification of Original Plant and Crude Herbs in Paris daliensis H. Li et V.G. Souku and Paris dulongensis H. Li et S. Kuritap

[Objectives] Via systematic comparative study on Paris daliensis and Paris dulongensis, the research aimed to provide test data for their character and microscopic identification. [Methods] Original plants, characters, microscopic identification of cross section and powder of rhizome were used. [Results] Microscopic characteristics of cross section and powder of rhizome were basically consistent with identification results of literature, and parenchyma cell of P. dulongensis had brown-red mass. [Conclusions] The research could provide reference basis for identification of authenticity and establishment of quality standards for original plants and medicinal materials of P. daliensis and P. dulongensis, and their further research and development.

Quality Standard of Zijinbiao

[Objectives]To establish the quality standard for Zijinbiao.[Methods]Microscopic identification,physical and chemical identification,and thin-layer chromatography(TLC)were used to qualitatively identify Zijinbiao.The moisture,total ash,acid-insoluble ash,and alcohol-soluble extract content were determined.The content of Plumbagin was determined by high performance liquid chromatography(HPLC).[Results]Microscopic identification,physical and chemical identification and thin layer identification features were remarkable.The moisture,total ash,acid-insoluble ash,and extract content of the 15 batches of samples were 7.49%-11.84%,2.43%-5.81%,0.59%-3.18%and 13.80%-20.45%,respectively.The linear equation of Plumbagin was Y=38094X,R^(2)=0.9996.Plumbagin had a good linear relationship in the range of 0.01-0.53 mg/mL.[Conclusions]This method is specific and reproducible,and can be used for quality control of Zijinbiao.

Chemical Composition of Artemisia subdigitata Mattf.

[Objectives] The aim was to study the chemical composition of the aboveground part of Artemisia subdigitata Mattf. [Methods]Using the systemic preparative test,the water extract,ethanol extract and petroleum ether extract of the aboveground part of A. subdigitata were subjected to physiochemical identification,and the contained chemical constituents were identified preliminarily. [Results] The preliminary comparisons of preparative test results of the aboveground part of A. subdigitata suggested that the whole plant may contain saponins,tannins,phenols,flavonoids,anthraquinones,coumarins,lactones,alkaloids,sterides or triterpenes,volatile oils and oils. [Conclusions]A. subdigitata contains a variety of chemical constituents. This study provides certain experimental basis for the further research and development and utilization of A. subdigitata.

Quality Standard of Yi Medicinal Material Anaphalis margaritacea

[Objectives]To establish quality standards for traditional Yi medicine of the Anaphalis margaritacea.[Methods]The original plants,traits,identification and TLC was used to identify L.franchetii Beauv.water content,total ash,acid-insoluble ash and extract were checked according to the Chinese Pharmacopoeia(2020 Edition).The content of 3,5-dicaffeoylquinic acid was determined by HPLC.[Results]The microscopic identification features are obvious,epidermal cells,stomata,non-glandular hairs,annular vessel,conduit wood fiber,pollen grains,starch grains,calcium oxalate clusters were observed,etc.TLC showed clear spots and good resolution.The extract content of acid-insoluble ash aqueous solution in 16 batches of samples was 5.22%-9.33%,6.79%-14.47%,0.39%-3.30%,20.49%-32.93%,respectively.3,5-O-dicafeylquinic acid showed good linear relationships within their own ranges(R^(2)=1.0),whose average recoveries were 99.11%with the RSD of 1.35%,respectively.[Conclusions]The method adopted was reasonable and feasible,and could be used for quality control of A.margaritacea.