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Experimental study on characteristics of trapping and regulating sediment with an open-type check dam in debris flow hazard mitigation

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Journal of Mountain Science 2018年第9期15卷 2001-2012页

作者： SUN Hao you yong LIU Jin-feng Key Laboratory of Mountain Hazards and Earth Surface Process Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China University of Chinese Academy of Sciences Beijing 100049China

Beam dams are a highly effective and commonly used open-type check dam in debris-flow hazard mitigation. In this study, dimensional analysis was used to obtain empirical equations for quantitatively determining the sediment-trapping and flow-regulating characteristics of a beam dam. To determine the coefficients of the empirical equations, flume experiments were conducted to simulate the trapping and regulating processes. The flow pattern, trapping, and regulating characteristics were investigated when debris flows passed through a beam dam. Debris-flow bulk density and peak discharge, and sediment-trapping ratios, were measured directly and indirectly. The results showed that three blocking actions occurred, and that blockage-breaking considerably influenced the trapping and regulating performance of the beam dam. The relative opening size and the sediment concentration were the two main factors affecting the performance of the beam dam. The ratio of trapping sediment decreased with relative opening, and increased with sediment concentration as well as reducing ratio of bulk density and reducing ratio of peak discharge. The sediment concentration and relative opening were the leading factors influencing the trapping and regulating sediment of a beam dam, followed by flume gradient. The results showed that the calculated values obtained using empirical equations were in good agreement with the values derived from the experiments, and that the deviation was acceptable. Finally, taking Zechawa Gully as an example, using the empirical equations we designed the opening size of a beam dam aimed to trap sediment and regulate peak discharge of debris flow in the main gully.

关键词： Debris flow Beam dam Flumeexperiment Trapping and regulating

Pylorus-preserving gastrectomy for early gastric cancer

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World Journal of Gastrointestinal Oncology 2024年第3期16卷 653-658页

作者： Ke-Kang Sun yong-you Wu Department of Gastrointestinal Surgery The Affiliated Kunshan Hospital to Jiangsu UniversitySuzhou 215300Jiangsu ProvinceChina Department of Gastrointestinal Surgery The Second Affiliated Hospital of Soochow UniversitySuzhou 215008Jiangsu ProvinceChina

Pylorus-preserving gastrectomy(PPG)has been widely accepted as a function-preserving gastrectomy for middle-third early gastric cancer(EGC)with a distal tumor border at least 4 cm proximal to the *** procedure essentially preserves the function of the pyloric sphincter,which requires to preserve the upper third of the stomach and a pyloric cuff at least 2.5 *** suprapyloric and infrapyloric vessels are usually preserved,as are the hepatic and pyloric branches of the vagus *** with distal gastrectomy,PPG has significant advantages in preventing dumping syndrome,body weight loss and bile reflux *** postoperative complications after PPG have reached an acceptable *** can be considered a safe,effective,and superior choice in EGC,and is expected to be extensively performed in the future.

关键词： Gastric cancer Pylorus-preserving gastrectomy Oncological safety Gastric stasis

Experimental study on blocking and self-cleaning behaviors of beam dam in debris flow hazard mitigation

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International Journal of Sediment Research 2018年第4期33卷 395-405页

作者： Hao Sun yong you Jinfeng Liu Key Laboratory of Mountain Hazards and Earth Surface Process Institute of Mountain Hazards and Environment Chinese Academy of Sciences University of Chinese Academy of Sciences

Blocking is one of the important features when a beam dam intercepts debris flow, while self-cleaning is another when managing suspended debris flow. Both features determine the debris flow control benefits of beam dam but the latter often is not considered in practical engineering design. In this paper, a series of specially designed flume experiments were done to simulate blocking and self-cleaning processes. The blocking ratio and deposition features were measured to contrast the blocking and self-cleaning performance before and after artificial self-cleaning. The experimental results reveal that the beam dam net opening, particle diameter of sediment, sediment concentration, and gradient of the channel are the main factors affecting blocking performance. A new criterion of blocking performance of beam dams that considers the interaction of multiple factors and can provide guidance to practical project design is proposed. For all three types of blocking, sediment deposited upstream of a beam dam can be effectively transported downstream by erosion from post-debris-flow floods, Self-cleaning performance is most efficient for temporary blocking, followed by partial-blocking, and total-blocking. The efficiency of selfcleaning largely depends on the change of the sediment deposit due to erosion. Finally, a discussion is given for the optimal design of an open-type check dam and the feasibility of synergistic effects of selfcleaning in combination with artificial cleaning. Some supporting artificial silt-cleaning should be implemented in practice. A beam dam will, thus, have more storage capacity with which to control the next debris flow event.

关键词： Debris flow Beam dam Critical blocking criterion Self-cleaning Flume experiment

Correlation of anaerobic ammonium oxidation and denitrification

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Journal of Environmental Sciences 2006年第2期18卷 227-231页

作者： ZHU Jing-ping HU yong-you LIANG Hui-qiang College of Environmental Science and Engineering South China University of Technology Guangzhou 510640 China College of Environment and Resources Engineering Southwest University Science and Technology Mianyang 621002 China

The feasibility of the nitrous organic wastewater treated was studied in seven anaerobic sequencing batch reactors（ASBRs）（0^#-6^#） which had been run under stable anaerobic ammonium oxidation （Anammox）. By means of monitoring and data analysis of COD, NH4^#-N, NO2^--N, NO3^--N and pH, and of microbial test, the results revealed that the optimal Anammox performance was achieved from 2^# reactor in which COD/NH4^＋ -N was 1.65, Anammox bacteria and denitrification bacteria could coexist, and Anammox reaction and denitrification reaction could occur simultaneously in the reactors. The ratio of NH4^＋-N consumed ： NO2^- -N consumed ： NO3^- -N produced was 1：1.38：0.19 in 0^# reactor which was not added glucose in the wastewater. When different ratio of COD and NH4^＋-N was fed for the reactors, the ratio of NO2^- -N consumed： NH4^＋-N consumed was in the range of 1.51-2.29 and the ratio of NO;-N produced： NH4^＋ -N consumed in the range of 0 -0.05.

关键词： anaerobic ammonium oxidation (Anammox) anaerobic sequencing batch reactor (ASBR) biological denitrification denitrification

A High-throughput Genomic Tool： Diversity Array Technology Complementary for Rice Genotyping

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Journal of Integrative Plant Biology 2006年第9期48卷 1069-1076页

作者： yong Xie Kenneth McNally Cheng-Yun Li Hei Leung you-yong Zhu National Center for Agro-biodiversity Yunnan Agricultural University Kunming 650201 China Genetic Resources Center International Rice Research Institute DAPO P.O. Box 7777 Metro Manila Philippines Entomology and Plant Pathology Division International Rice Research Institute DAPO P.O. Box 7777 Metro Manila Philippines

Diversity array technology （DART^TM） was a genotyping tool characterized gel-independent and high throughput. The main purpose of present study is to validate DArT for rice （Oryza sativa L.）genotyping in a high throughput manner. Technically, the main objective was to generate a rice general purpose gene pool, and optimize this genomic tool in order to evaluate rice germplasm genetic diversity. To achieve this, firstly, a generalpurpose DArT array was developed. Ten representatives from 24 varieties were hybridized with the general-purpose array to determine the informativeness of the clones printed on the array. The informative 1 152 clones were re-arrayed on a slide and used to fingerprint 17 of 24 germplasms. Hybridizing targets prepared from the germplasm to be assayed to the DNA array gave DNA fingerprints of germplasms. Raw data were normalized and transformed into binary data, which were then analyzed by using NTSYSpc （Numerical taxonomy system for cluster and ordination analysis, v. 2.02j） software package. The graphically displayed dendrogram derived from the array experimental data was matched with simple sequence repeats genotyping outline and varieties＇ pedigree deviation of the different varieties. Considering DArT is a sequence-independent genotyping approach, it will be applied in studies of the genetic diversity and the gene mapping of diverse of organisms, especially for those crops with less-developed molecular markers.

关键词： amplified fragment length polymorphisms diversity array technology genome complexity reduction microarray rice genotyping

Mutations in components of the Wnt signaling pathway in gastric cancer

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World Journal of Gastroenterology 2008年第10期14卷 1570-1574页

作者： Kai-Feng Pan Wan-Guo Liu Lian Zhang Wei-Cheng you you-yong Lu Department of Cancer Epidcmiology Peking University School of Oncology and Beijing Cancer Hosp-ital & Institute Beijing 100036 China Div-ision of Experimenlal Pathology Department of Laboratory Medicine and Pathology Mayo Clinic/Mayo Medical School Rochester 55905 United States Beijing Laboratory of Molecular Ontology Peking University School of Oncology and Beijing Cancer Hospital & Institute Beijing 100036 China

AIM: To explore the contribution of AXIN1, AXIN2 and beta-catenin, components of Wnt signaling pathway, to the carcinogenesis of gastric cancer (GC), we examined AXIN1, AXIN2 exon7 and CTNNB1 (encoding beta- catenin) exon3 mutations in 70 GCs. METHODS: The presence of mutations was identified by polymerase chain reaction (PCR)-based denaturing high-performance liquid chromatography and direct DNA sequencing. Beta-catenin expression was detected by immunohistochemical analysis. RESULTS: Among the 70 GCs, 5 (7.1%) had mutations in one or two of these three components. A frameshift mutation (1 bp deletion) in exon7 of AXIN2 was found in one case. Four cases, including the case with a mutation in AXIN2, had frameshift mutations and missense mutations in AXIN1. Five single nucleotide polymorphisms (SNPs), 334 C>T, 874 C>T, 1396 G>A, 1690 C>T and 1942 T>G, were identified in AXIN1. A frameshift mutation (27 bp deletion) spanning exon3 of CTNNB1 was observed in one case. All four cases with mutations in AXIN1 and AXIN2 showed nuclear beta- catenin expression. CONCLUSION: These data indicate that the mutationsin AXIN1 and AXIN2 may contribute to gastric carcino- genesis.

关键词： AXIN1 AXIN2 β-catenin Wnt signaling pathway Gastric cancer

Spatial-temporal distribution of debris flow impact pressure on rigid barrier

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Journal of Mountain Science 2019年第4期16卷 793-805页

作者： LIU Dao-chuan you yong LIU Jin-feng LI yong ZHANG Guang-ze WANG Dong Key Laboratory of Mountain Hazards and Earth Surface Processes and Institute of Mountain Hazards and Environment Chinese Academy of Sciences University of Chinese Academy of Sciences China Railway Eryuan Engineering Group co. LTD

Grain composition plays a vital role in impact pressure of debris flow. Current approaches treat debris flow as uniform fluid and almost ignore its granular effects. A series of flume experiments have been carried out to explore the granular influence on the impact process of debris flow by using a contact surface pressure gauge sensor(Tactilus~?, produced by Sensor Products LLC). It is found that the maximum impact pressure for debris flow of low density fluctuates drastically with a long duration time while the fluctuation for flow of high density is short in time, respectively presenting logarithmic and linear form in longitudinal attenuation. This can be ascribed to the turbulence effect in the former and grain collisions and grainfluid interaction in the latter. The horizontal distribution of the impact pressure can be considered as the equivalent distribution. For engineering purposes, the longitudinal distribution of the pressure can be generalized to a triangular distribution, from which a new impact method considering granular effects is proposed.

关键词： Debris flow Impact force Grain composition Spatio-temporal distribution Dynamic coefficient

PEN/BADCy Interlayer Dielectric Films with Tunable Microstructures via an Assist of Temperature for Enhanced Frequency Stability

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Chinese Journal of Polymer Science 2020年第11期38卷 1258-1266,I0009页

作者： Xi-Ting Lei Li-Fen Tong Ming-Zhen Xu yong you Xiao-Bo Liu School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 610054China

Low dielectric in terlayer films have become an important element to ensure the development of the microelectr onics industry.A kind of flexible interlayer dielectrics,polyarylene ether nitrile/bisphenol A cyanate ester(PEN/BADCy)film,with good thermal stability and low frequency dependence,has been developed by solution casting ***,materials were designed to incorporate bisphenol A cyanate ester as a part of blend,contributing to the frequency stability and structural *** morphological study combined with electron microscopy revealed the uniform and flexible microstructure information with controllable morphology through self-polymerization of cyanate esters with different prepolymerization time and curing *** dielectric films could present high thermal stability with Tg>180℃.Significant improvement in the dielectric properties was achieved for the dielectric constant and loss was much stabler than neat PEN over the frequency range from 100 Hz to 5 *** the prepolymerization time was 3h and final curing temperature reached 230℃,the dielectric constant and dielectric loss of the films were 3.36 and 0.013 at 100 kHz,*** dimensional stability(CTE=53.67×10^-6 K^-1)was confirmed and con sidered beneficial to use as an in terlayer dielectrics.

关键词： Polyarylene ether nitrile Bisphenol A cyanate ester Interlayer dielectrics Tunable microstructures

Impact pressure of debris flow on beam dam

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Journal of Mountain Science 2023年第10期20卷 2822-2834页

作者： WANG Dong-wei you yong LIU Jin-feng SUN Hao WANG Zhuang Key Laboratory of Mountain Hazards and Earth Surface Process Chinese Academy of SciencesChengdu 610041 China Institute of Mountain Hazards and Environment CASChengdu 610041China University of Chinese Academy of Science Beijing 100049China

The use of open-type check dams in mountainous areas has become common practice in order to mitigate the effects of debris flow and extend the service life of engineering *** beam dam,a common debris flow control system,has received less attention in research on the impact process of debris flow and check dams compared to solid check ***,the estimation of impact pressure in debris flow primarily considers debris flow characteristics,without taking into account the influence of geometric characteristics of the transmission *** better understand the impact process of debris flow on beam dams,a series of small-scale debris flow impact tests were conducted in a model *** parameters,including velocity,depth,and impact pressure,were *** results show that the maximum impact pressure of debris flow is affected by both the characteristics of the debris flow and the relative opening size of the beam *** to flow and edge occlusion in the middle of the beam dam,the discharge of debris flow is enhanced,resulting in a longer impact process and higher maximum impact *** on these findings,a calculation model of the maximum impact pressure of debris flow at the midpoint of the middle beam is proposed,which can be used to estimate the impact of debris flow on the discharge part of the beam dam.

关键词： Debris flow Beam dam Impact pressure Relative opening size Calculation model