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Mechanisms of root-soil reinforcement in bioembankments of sloping farmland in the purple hilly area,China

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Journal of Mountain Science 2019年第10期16卷 2285-2298页

作者： JIN Hui-fang SHI Dong-mei ZENG Xiao-ying WANG San-shu DUAN Teng LOU Yi-bao College of Resources and Environment Institute of Soil and Water Conservation and Eco-environmentSouthwestUniversityChongqing400715China Chongqing Institute of Forest Science Chongqing400036China Chongqing Surveying and Design Institute of Water Resources Electric Power and ArchitectureChongqing400020China

Bio-embankment is an important soil and water conservation measure in the purple hilly area in China,which can effectively improve the ability of cultivated soil layers to resist rainfall erosion and runoff *** contrast,the ecological effect of bioembankment depends on the stability of the earth *** the natural grass bank as a control(CK),the root distribution,root tensile properties and shear resistance of root-soil composites for 3 typical soil and water conservation bio-embankments,namely,Morus alba Linn(Morns),Zanthoxylum bungeanum Maxim(Zanthoxylum)and Medicago sativa(Medicago)were *** results included the following:(1)The root system of the bio-embankments generally decreased in extent with the soil depth;fine roots in the o-io cm depth were most prevalent and significantly higher than those at the other depths,and coarse roots were mainly distributed in the o-30cm layer.(2)The stress-strain curves of the roots of each bio-embankment were single-peak curves without clear strain softening *** smaller the root diameters were,the smoother the stress-strain curves,and the lower the capability of the earth bank to resist *** larger the root diameters were,the lower the tensile *** average root tensile force was highest for Zanthoxylum(73.91 N),followed by Medicago(68.07N)and Morus(61.88 N),and the average root tensile strength showed the same trend,16.52 MPa for Zanthoxylum,16.08 MPa for Medicago and 13.02MPa for Morus.(3)The bio-embankment measures significantly improved the soil shear resistance,especially under vertical loads of 1oo kPa and *** soil internal friction angle showed a significant log-positive correlation with root morphological parameters of root length density(RLD),root surface area density(RSAD) and rootweight density(RWD),while the soil cohesion force showed a positive linear correlation with these *** results provide effective parameters supporting for the design of bio-embankm

关键词： Bio-embankments Root distribution Tensile properties Shear strength Earth bank collapse purple hilly area

Photocycle of 13-cis-retinal in bacteriorhodopsin caused by destruction to the cooperative effect of purple membrane

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Science China Chemistry 1998年第2期41卷 135-141页

作者：胡坤生何靳安张衡涛 Department of Cell Biology Institute of Biophysics Chinese Academy of Sciences Beijing China

The steady absorption and kinetic changes of M 412 intermediate of the light and dark adapted bacteriorhodopsin (BR) solubilized by different concentrated Triton X 100 were investigated. The results indicated that the cooperative effect existing within the trimeric BR of native purple membrane (PM) was damaged in the system containing the surfactant since the component and structure of the bilayer lipid membrane in PM varied due to the solubilization of partial PM lipids by Triton X 100. The destruction to the cooperative effect of BR ultimately caused 13 cis retinal of the dark adapted BR to take part in BR photocycle and also to generate the deprotonated M 412 intermediate.

关键词： bacteriorhodopsin purple membrane cooperative effect Triton X 100 M 412 intermediate.

Drying characteristics, functional properties and in vitro digestion of purple potato slices dried by different methods

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Journal of Integrative Agriculture 2019年第9期18卷 2162-2172页

作者： QIU Gan JIANG Yong-li DENG Yun Department of Food Science and Technology Shanghai Jiao Tong University

The drying characteristics,physico-chemical and functional properties,as well as starch digestibility,of purple potato slices dried using different methods(such as,vacuum freeze-drying,VFD;hot-air drying,HAD;air-impingement jet drying,AIJD;and far-infrared assisted heat-pump drying,FIHPD)were *** rate was the highest(3.0 g 100 g^-1 min^-1)using AIJD,followed by FIHPD and HAD,and the rate of VFD was the lowest one(0.3 g 100 g^-1 min^-1).Drying data were fitted to 12 thin-layer drying models,with the Midilli model giving the best ***,AIJD showed higher diffusivity(5.5×10^-10 m^2 s^–1)and energy efficiency(55 J g^-1)than any other drying method used in this *** reference to the samples dried by VFD,the starch granules of the samples obtained by HAD,FIHPD,and AIJD exhibited different extent of disruption,which significantly increased their water absorption capacity,swelling power,and in vitro digestibility,but decreased the peak *** sample resulting from AIJD had the greatest water absorption capacity(7.9 g g^-1)and solubility(21.6%),but the smallest syneresis rate(48%).Good correlation coefficients(R^2>0.98)implied that the pseudofirst order kinetic model adequately described the rate and extent of starch digestion of dried potato *** from AIJD and FIHPD showed the highest digestibility percentages,reaching to 72.4 and 72.5%.Based on the drying rate,specific energy consumption,functional properties and digestibility,AIJD appeared to be quite effective and suitable to be transferred on the industry scale.

关键词： purple potato air-impingement jet drying(AIJD) drying characteristics flour properties starch digestibility

Investigation of structural change of purple membrane in storage by transmission electron microscope and atomic force microscope

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Chinese Science Bulletin 2001年第20期46卷 1753-1756页

作者： LI Xiaodong LI Zongli YAN Jiusheng LI Hui HAN Baoshan HU Kunsheng WANG Aojin Center of Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100080China State Key Laboratory of Magnetism Institute of PhysicsChinese Academy of SciencesBeijing 100080China Photosynthesis Research Center Institute of BotanyChinese Academy of SciencesBeijing 100093China Institute of Biophysics Chinese Academy of SciencesBeijing 100101China

The structural change of purple membrane during storage has been investigated by means of transmission electron microscope and atomic force microscope. It is found that many liposomes have spontaneously evolved from the purple membrane sheets isolated three years ago. The membrane proteins on the liposomes, bacteriorhodopsin, are still presented as trimers in 2-D hexagonal structure, which is the same as that in natural cell membrane. However, the cytoplasmic surface of purple membrane faced outside on the liposomes.

关键词： transmission electron microscope (TEM) atomic force microscope (AFM) purple membrane (PM) bacteriorhodopsin (BR).

Anti-scourability of purple soil on hillslopes with different land uses

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Science China(Technological Sciences) 2003年第Z1期46卷 133-141页

作者： ZHANG Jianhui, LIU Gangcai, NI Shijun, ZHU Bo & GE Fanglong Institute of Mountain Hazards and Environment, Chinese Academy of Sciences and Ministry of Water Resources, Chengdu 610041, China Chengdu University of Technology, Chengdu 610059, China Chinese Acad Sci Inst Mt Hazards & Environm Chengdu 610041 Peoples R China Minist Water Resources Chengdu 610041 Peoples R China Chengdu Univ Technol Chengdu 610059 Peoples R China

A large-scale flume (40 cm×10 cm×10 cm) was used to determine soil anti-scourability of 4 different land uses of purple soil in hilly areas of Sichuan, China under artificial removal of vegetation to examine the effects of land uses on sediment production by runoff. The results showed that soil anti-scourability declined with the increase of slope gradients in the form of power function, but there was a significant difference in the effects of slope gradients on anti-scourability between different land uses. The ratio of the mean values of soil anti-scourability was 1︰2.2︰2.5︰3.6 for forest land, new waste pasture, old waste pasture, crop land respectively, indicating that forest and grass use can significantly improve soil anti-scourability. Compared with the observations from the runoff plots located at the same sites in this region, an inconsistent result was found between anti-scourability and anti-erodibility in hilly areas of Sichuan. Essential causes of the differences in soil anti-scourability were further discussed based on analyzing the influence of inherent soil characteristics induced by different land uses on soil anti-scourability.

关键词： sediment yield, soil anti-scourability, land use, vegetation, purple soil.

One new purple membrane protein (D1201)

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Chinese Science Bulletin 1996年第9期41卷 766-769页

作者：胡坤生张衡涛张克谈曼琪田心玉周培瑾 Institute of Microbiology Chinese Academy of Sciences Beijing 100080 China Institute of Biophysics Chinese Academy of Sciences

Stoeckenius found the bacteriorhodopsin in purple membrane in the 1970s. Sinee then,much work has been done about the structure, function and application of molecular elec-tronics. In the late 1980s, the application of genetic engineering in molecular biology en-abled us to further understand the function of proton pump of purple membrane, but so far,

关键词： H. halobinm D1201 purple membrane protein proton pump.

The interaction between purple membrane and membrane lipid

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Chinese Science Bulletin 2002年第7期47卷 562-564页

作者： HU KunshengInstitute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China (e-mail: huks1401@ ***) Institute of Biophysics Chinese Academy of Sciences Beijing China

Bacteriorhodopsin in purple membrane was reconstituted into different lipid vesicles. The effect of three different lipids on the structure and function of bacteri-orhodopsin in lipid vesicles was studied by the observation on freeze-fracture eletron microscopy, the rotational diffusion of bacteriorhodopsin in lipid vesicles, the measurement of absorption spectrum, and the absorbance change with time. For these prepared samples, the results showed that DMPC was the stable lipid environment of bacteriorhodopsin; egg-pc causeed the loss of retinal chromophore of bacteriorhodopsin and it was not reversible change, cholesterol could stabilize the bacteriorhodopsin in lipid environment, but it caused the aggregation of bacteriorhodopsin.

关键词： purple membrane bacteriorhodopsin (BR) lipid vesicle.

Interactions between purple membrane and melittin

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Chinese Science Bulletin 1995年第12期40卷 1033-1037页

作者：张衡涛胡坤生 Institute of Biophysics Chinese Academy of Sciences Beijing 100101 China

The purple membrane (PM) is found on the plasma membrane of Halobacteria Halobium,which contains an integral membrane protein, bacteriorhodopsin (BR). The structure andfunction of bacteriorhodopsin are rather clear at present. Protein to lipid ratio of the purplemembrane is 1:10 (mol/mol). Most of lipids of purple membranes are negatively charged atneutral pH.

关键词： purple membrane bacteriorhodopsin melittin intrinsic fluorescence.

Measurement of K, L intermediate lifetime of purple membrane excited by nanosecond laser pulse

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Chinese Science Bulletin 1995年第21期40卷 1834-1837页

作者：陈志坚胡坤生姚德成施桦 Department of Physics Graduate School Science and Technology University of China Beijing 100039 China Institute of Biophysics Chinese Academy of Sciences Beijing 100101 China

purple membrane, molecular weight 26ku, is synthesized by Holobacterium halobium on some parts of its cell membrane under a special condition combined by 248 residues,and 7 times acrossing membrane. Only one kind of protein, bacteriorhodopsin (BR), is on the membrane. After light excitation, BR goes through a series of intermediate processes K, L, M, N, O and recovers to BR. purple membrane is an ideal biomaterial for photo energy transfer, and becomes a new focus field of many branches of science. Because the photocycle of BR is related to light-driven proton pump and photoelectric response,

关键词： purple membrane photokinetic process nanosecond YAG laser.