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Journal of Mountain Science 2015年第1期12卷 60-69页

作者： liu jun-feng CHEN Ren-sheng WANG Gang Qilian Alpine Ecology and Hydrology Research Station Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Heihe Key Laboratory of Ecohydrology and Integrated River Basin Management Chinese Academy of Sciences

Snowline change and snow cover distribution patterns are still poorly understood in steep alpine basins of the Qilian Mountainous region because fast changes in snow cover cannot be observed by current sensing methods due to their short time scale. To address this issue of daily snowline and snow cover observations, a ground- based EOS 7D camera and four infrared digital hunting video cameras （LTL5210A） were installed around the Hulugou river basin （HRB） in the Qilian Mountains along northeastern margin of the Tibetan Plateau （38°15′54″N, 99°52′53″E） in September 2011. Pictures taken with the EOS 7D camera were georeferenced and the data from four LIL521oA cameras and snow depth sensors were used to assist snow cover estimation. The results showed that the time-lapse photography can be very useful and precise for monitoring snowline and snow cover in mountainous regions. The snowline and snow cover evolution at this basin can be precisely captured at daily scale. In HRB snow cover is mainly established after October, and the maximum snow cover appeared during February and March. The consistent rise of the snowline and decrease in snow cover appeared after middle part of March. This melt process is strongly associated with air temperature increase.

关键词： Time-lapse camera Snow cover Snowline Hulugou river basin Qilian Mountain

Surface energy balance of Bayi Ice Cap in the middle of Qilian Mountains,China

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Journal of Mountain Science 2018年第6期15卷 1229-1240页

作者： QING Wen-wu HAN Chun-tan liu jun-feng Key Laboratory of Western China＇s Environmental Systems （Ministry of Edueation） College of Earth and Environmental Sciences Lanzhou University Lanzhou 730000 China Northwest Institute of Eeo-Environment and Resources Chinese Academy of Sciences Lanzhou 730000 China

Energy balance at the glacier surface is important for understanding the impacts of climate change on glaciers. Here, we analyzed the characteristics of the glacier surface energy fluxes along with their contributions to glacier melt on Bayi Ice Cap in Qilian Mountains by using a point-scale energy balance model. The half-hourly meteorological data from an automatic weather station(AWS) located on the glacier was used to drive the energy balance model. The model simulated results could accurately represent the mass-balance observations from the stake near the weather station during summer 2016. Our results showed the net radiation(86%) played an important role in the surface energy balance, and the contribution of the turbulent heat fluxes(14%) to the energy budget was relatively less important. A distinct behavior of energy balance, as compared to other continental glaciers in China(e.g., two adjacent glaciers Laohugou No. 12 Glacier and Qiyi Glacier), is the fact that a sustained period of positive turbulent latent flux exists on Bayi Ice Cap during August, causing faster melt rate in the month of August. Our study also presented the effect of frequent summer snowfall in slowing down surface melt by changing the surface albedo during the beginning of the melting season.

关键词： Surface melting Energy balance Turbulent latent flux Summer snowfall Glacier

Precipitation Type Estimation and Validation in China

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Journal of Mountain Science 2014年第4期11卷 917-925页

作者： CHEN Ren-sheng liu jun-feng SONG Yao-xuan Qilian Alpine Ecology & Hydrology Research Station Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Key Laboratory of Inland River Ecohydrology Chinese Academy of Sciences

The results from three methods aimed at improving precipitation type （e.g., rain, sleet, and snow） estimation are presented and compared in this paper. The methods include the threshold air temperature （AT）, threshold wet bulb temperature （WBT） and Koistinen and Saltikoff （KSS） methods. Dot graphs are plotted to acquire the threshold air temperature or the threshold wet bulb temperature using daily averaged air temperature, wet bulb temperature and precipitation data at 643 stations from 1961 to 1979 （precipitation types are not labeled in the database from 1980 to present） in China. The results indicate that the threshold AT or WBT methods are not able to differentiate rain, sleet and snow in the most regions in China; sleet is difficult to differentiate from other precipitation types based on the two threshold methods. Therefore, one threshold AT and WBT method was used in this study to differentiate rain and snow. Based on Gaussian- Kriging interpolation of threshold air temperature （To） and wet bulb temperature （Tw）, the To and Tw contour lines and contour surfaces are calculated for China. Finally, a comparison between the KSS, AT and WBT methods are provided in which the KSS method is calculated based on air temperature and relative humidity. The results suggest that the KSS method is more appropriate for water phase estimation than are the other methods; the maximum precision for rain and snow is 99% and 94%, respectively. The AT method performs better than the WBT method when the critical air temperature is 2℃.

关键词： Threshold temperature Wet bulbtemperature Precipitation type Hydrologicalprocesses

Experimental study of enhancing coalbed methane recovery by carbon dioxide injection driving methane

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Journal of Coal Science & Engineering(China) 2010年第4期16卷 356-361页

作者： LUO Dao-cheng liu jun-feng School of Chemistry and Technology Hunan University of Science and Technology Xiangtan 411201 China

In order to enhance coalbed methane recovery, taking a self-developed largecalesimulation system for the platform, a modeling experiment of driving CH_4 by CO_2 gasinjection was *** results of experiment indicates that there is a significant lag effectof adsorption and desorption on gas, the gas pressure is changed more rapidly in theprocess of carbon dioxide adsorption of coal than methane adsorption of coal; After theinjection of carbon dioxide, compare with methane single *** an early stage,speed and amount of methane single desorption are greater than the speed and amountof displacement desorption, the speed and amount of displacement desorption *** the process of replacement, CH_4 concentration constantly declined, while CO_2concentration constantly *** the process of CO_2 gas injection, the temperature of coalhave been significantly increased, it is more beneficial to make CH_4 gas molecules becomefree from the adsorbed state when temperature is *** the pressurestep-down at the same rate, using the method of CO_2 driving CH_4, compared with themethod of conventional pressure step-down, the desorption rate of CH_4 in coal can beraised about 2.13 times, at the same time, a lot of greenhouse gas CO_2 will also be buriedin the ground, there is a very significant environmental benefit.

关键词： carbon dioxide injection replacement experiment coalbed methane desorption methane recovery

Combined optical fiber interferometric sensors for the detection of acoustic emission

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Optoelectronics Letters 2008年第3期4卷 184-187页

作者： LIANG Yi-jun MU Lin-lin liu jun-feng YU Xiao-tao College of science Harbin Engineering University Harbin 150001 China

A type of combined optical fiber interferometric acoustic emission sensor is proposed. The sensor can be independent on the laser source and make light interference by matching the lengths of two arms,so it can be used to monitor the health of large structure. Theoretical analyses indicate that the system can be equivalent to the Michelson interferometer with two optical fiber loop reflectors,and its sensitivity has been remarkably increased because of the decrease of the losses of light energy. PZT is powered by DC regulator to control the operating point of the system,so the system can accurately detect feeble vibration which is generated by ultrasonic waves propagating on the surface of solid. The amplitude and the frequency of feeble vibration signal are obtained by detecting the output light intensity of interferometer and using Fourier transform technique. The results indicate that the system can be used to detect the acoustic emission signals by the frequency characteristics.

关键词： Acoustic emissions Acoustics Electric network analysis Fiber optics Fibers Fourier transforms Geodetic satellites Interferometers Interferometry Lattice vibrations Light sources Michelson interferometers Optical fibers Optical in Acoustic emission sensors Acoustic Emission signals Fiber loop reflectors Fourier Frequency characteristics Interferometric sensors Laser sources Light energy Light intensities Operating points Optical Vibration signals

Application of hepatitis B virus replication mouse model

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World Journal of Gastroenterology 2010年第16期16卷 1979-1985页

作者： Gao, Zhan liu, feng-jun liu, Li Zhou, Tao-You Lei, jun Xu, Lu liu, Cong Dai, Jie Chen, En-Qiang Tang, Hong W China Hosp Sichuan Univ Ctr Infect Dis Chengdu 610041 Sichuan Prov Peoples R China Sichuan Univ Div Infect Dis State Key Lab Biotherapy Chengdu 610041 Sichuan Prov Peoples R China N Sichuan Med Coll Affiliated Hosp Dept Infect Nanchong 637000 Sichuan Prov Peoples R China

AIM:To evaluate the value of the hepatitis B virus(HBV) replication mouse model with regard to several aspects of the study of HBV ***:To evaluate the HBV replication mouse model in detecting the efficacy of anti-HBV agents,the interferon inducer polyinosinic-polytidylin acid(polyIC) and nucleotide analogues adefovir and entecavir were administered to mice injected with wild type pHBV4.1,and the inhibiting effect of these agents on HBV DNA replication was *** identify the model's value in a replication ability study of HBV drug-resistant mutants and a HBx-minus mutant,telbivudine resistance mutants(rtM204I,ayw subtype),adefovir resistance mutants(rtA181V + rtN236T,ayw subtype) and HBxminus mutants were injected respectively,and their corresponding HBV DNA replication intermediates in mouse liver were ***:Compared with the wild type HBV replication mouse model without antiviral agent treatment,the HBV DNA replication intermediates of the polyICtreated group were decreased 1-fold;while in the entecavir-and adefovir-treated groups,the levels of HBV DNA replication intermediates were inhibited 13.6-fold and 1.4-fold,*** the mouse models injected with telbivudine resistance mutant,adefovir resistance mutant and HBx-minus mutant,HBV DNA replication intermediates could still be detected,but the levels of HBV DNA replication intermediates of these mutants decreased 4.5-fold,5.6-fold and 2.9-fold respectively,compared with the mouse model with wild type HBV ***:The HBV replication mouse model we established was a useful and convenient tool to detect the efficacy of antiviral agents and to study the replication ability of HBV mutants in vivo.

关键词： Hepatitis B virus Antiviral agents Drug resistance Mutants Mouse model

Acute extensive portal and mesenteric venous thrombosis after splenectomy:Treated by interventional thrombolysis with transjugular approach

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World Journal of Gastroenterology 2009年第24期15卷 3038-3045页

作者： Mao-Qiang Wang Han-Ying Lin Li-Ping Guo feng-Yong liu feng Duan Zhi-jun Wang Department of Interventional Radiology Chinese PLA General Hospital Beijing 100853 China

AIM:To present a series of cases with symptomatic acute extensive portal vein(PV)and superior mesenteric vein(SMV)thrombosis after splenectomy treated by transjugular intrahepatic approach catheter-directed thrombolysis. METHODS:A total of 6 patients with acute extensive PV-SMV thrombosis after splenectomy were treated by transjugular approach catheter-directed thrombolysis. The mean age of the patients was 41.2 *** access to the portal system via the transjugular approach,pigtail catheter fragmentation of clots, local urokinase injection,and manual aspiration thrombectomy were used for the initial treatment of PV-SMV thrombosis,followed by continuous thrombolytic therapy via an indwelling infusion catheter in the SMV,which was performed for three to six days. Adequate anticoagulation was given during treatment, throughout hospitalization,and after discharge. RESULTS:Technical success was achieved in all 6 *** improvement was seen in these patients within 12-24 h of the *** complications were *** 6 patients were discharged 6-14 d(8±2.5 d)after *** mean duration of follow-up after hospital discharge was 40±16.5 *** and contrast-enhanced computed tomography confirmed patency of the PV and SMV,and no recurrent episodes of PV-SMV thrombosis developed during the follow-up period. CONCLUSION:Catheter-directed thrombolysis via transjugular intrahepatic access is a safe and effective therapy for the management of patients with symptomatic acute extensive PV-SMV thrombosis.

关键词： Mechanical thrombectomy Portal vein Splenectomy Superior mesenteric vein Thrombolysis Thrombosis

Spatial variability of soil hydraulic conductivity and runoff generation types in a small mountainous catchment

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Journal of Mountain Science 2020年第11期17卷 2724-2741页

作者： YANG Yong CHEN Ren-sheng SONG Yao-xuan HAN Chun-tan liu Zhang-wen liu jun-feng Qilian Alpine Ecology and Hydrology Research Station Key Laboratory of Ecohydrology Inland River BasinNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China College of Urban and Environmental Sciences Northwest UniversityXi'an 710127China

As an important soil property,saturated hydraulic conductivity(Ks)controls many hydrological processes,such as runoff generation types,soil moisture storage and water *** of the extremely harsh natural environmental conditions and soil containing a significant fraction of gravel fragments in high-elevation mountainous catchments,the measurement data of Ks and other soil properties are seriously lacking,which leads to poor understanding on its hydrological processes and water *** this study,the vertical variation(0-150 cm)of Ks and other soil properties from 38 soil profiles were measured under five different land cover types(alpine barren,forest,marshy meadow,alpine shrub and alpine meadow)in a small catchment in Qilian Mountains,northwestern China.A typical characteristic of soil in mountainous areas is widespread presence of rock and gravel,and the results showed that the more rock and gravel in the soil,the higher Ks and bulk density and the lower the soil capillary porosity,field water capacity and total *** Ks of the lower layer with rock and gravel(18.49±10.22 mm·min-1)was significantly higher than that of the upper layer with relatively fine textured soil(0.18±0.18 mm·min-1).The order of values of the Ks in different land cover types was alpine barren,forest,alpine shrub,marshy meadow and alpine meadow,and the values of the Ks in the alpine barren were significantly higher than those of other land *** rainfall events in the research catchment had low rain intensity(<0.04 mm·min-1),and deep percolation(DP)was the dominant runoff generation *** the rainfall intensity increased(0.11 mm·min-1),subsurface stormflow(SSF)appeared in the alpine *** excess overland flow(IOF),SSF and DP existed simultaneously only when the rainfall intensity was extremely high(1.91 mm·min-1).IOF and SSF were almost never appeared in the alpine barren because of high *** alpine barren was the main runoffcontributed area in the

关键词： Saturated hydraulic conductivity Rock fragment Land cover Runoff generation Mountain catchment

New methods for calculating bare soil land surface temperature over mountainous terrain

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Journal of Mountain Science 2017年第12期14卷 2471-2483页

作者： YANG Yong CHEN Ren-sheng SONG Yao-xuan liu jun-feng HAN Chun-tan liu Zhang-wen Qilian Alpine Ecology and Hydrology Research Station Key Laboratory of Ecohydrology Inland River Basin Northwest Institute of Eco-Environment and Resources Chinese Academy of Sciences

Land surface temperature(LST) causes the phase change of water, links to the partitioning of surface water and energy budget, and becomes an important parameter to hydrology, meteorology, ecohydrology, and other researches in the high mountain cold regions. Unlike air temperature, which has common altitudinal lapse rates in the mountainous regions, the influence of terrain leads to complicated estimation for soil LST. This study presents two methods that use air temperature and solar position,to estimate bare LST with high temporal resolution over horizontal sites and mountainous terrain with a random slope azimuth. The data from three horizontal meteorological stations and fourteen LST observation fields with different aspects and slopes were used to test the proposed LST methods. The calculated and measured LST were compared in a range of statistical analysis, and the analysis showed that the average RMSE(root mean square error),MAD(mean absolute deviation), and R^2(correlation coefficient) for three horizontal sites were 5.09℃,3.66℃, 0.92, and 5.03℃, 3.52℃, 0.85 for the fourteen complex terrain sites. The proposed methods showed acceptable accuracy, provide a simple way to estimate LST, and will be helpful for simulating the water and energy cycles in alpine mountainous terrain.

关键词： Land surface temperature Air temperature Solar position Mountainous terrain

Effect of electroacupuncture at Sibai on the gastric myoelectric acitivities of denervated rats

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World Journal of Gastroenterology 2006年第36期12卷 5897-5901页

作者： Xiao-Rong Chang Jie Yan Yan-Ling Zhao Jiang-Shang Li Jian-Hua liu jun-feng He College of Acupuncture and Massage Hunan University of Traditional Chinese Medicine Changsha 410007 Hunan Province China

AIM： To explore the mechanism of the exciting effects of electro-acupuncture （EA） at Sibai on the gastric myoelectric activities. METHODS： A total of 32 rats were randomly divided into four groups. Through intraperitoneal injection with atropine （the anti-cholinergic agent by blockade of muscarinic receptors）, hexarnethonium （automatic nerve ganglion-blocking agent） and reserpine （anti-adrenergic agent by depleting the adrenergic nerve terminal of its norepinephrine store）, effects of EA at Sibai on the gastric myoelectric activities of the denervated rats were observed. RESULTS： After intraperitoneal injection of atropine and hexamethonium, the average amplitude and ratio of period to time in the phase of high activity of gastric myoelectric slow wave, and the average numbers of the peaks of gastric myoelectric fast wave were significantly decreased （P 〈 0.01, P 〈 0.05, P 〈 0.01）, while after intraperitoneal injection of reserpine, the aforementioned three parameters were increased （P 〈 0.01, P 〈 0.05, P 〈 0.01）. EA at Sibai point partially relieved the inhibitory effect of atropine and hexamethonium on the gastric myoelectric activities in the rats （P 〈 0.05 or P 〉 0.05）. CONCLUSION： Cholinergic and adrenergic nervous systems and autonomic nerve ganglion participate in the peripheral passage of the controlling effects of EA at Foot Yangming Channel on gastrointestinal tract.

关键词： Electro-acupuncture Rats Sibai Nerve block Gastric myoelectric activities