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| 1 | Linking vegetation cover patterns to hydrological responses using two process-based pattern indices at the plot scale显示文摘Vegetation cover pattern is one of the factors controlling hydrological processes.Spatially distributed models are the primary tools previously applied to document the effect of vegetation cover patterns on runoff and soil erosion.Models provide precise estimations of runoff and sediment yields for a given vegetation cover pattern.However,difficulties in parameterization and the problematic explanation of the causes of runoff and sedimentation rates variation weaken prediction capability of these models.Landscape pattern analysis employing pattern indices based on runoff and soil erosion mechanism provides new tools for finding a solution.In this study,the vegetation cover pattern was linked with runoff and soil erosion by two previously developed pattern indices,which were modified in this study,the Directional Leakiness Index(DLI)and Flowlength.Although they use different formats,both indices involve connectivity of sources areas(interpatch bare areas).The indices were revised by bringing in the functional heterogeneity of the plant cover types and the landscape position.Using both artificial and field verified vegetation cover maps,observed runoff and sediment production on experiment plots,we tested the indices’efficiency and compared the indices with their antecedents.The results illustrate that the modified indices are more effective in indicating runoff at the plot/hillslope scale than their antecedents.However,sediment export levels are not provided by the modified indices.This can be attributed to multi-factor interaction on the hydrological process,the feedback mechanism between the hydrological function of cover patterns and threshold phenomena in hydrological processes. | LIU Yu FU BoJie Lü YiHe GAO GuangYao WANG Shuai ZHOU Ji | 2013 | Science China Earth Sciences2013，56，11： | 15 |
| 2 | Synergistic effect of N- and F-codoping on the structure and photocatalytic performance of TiO_2显示文摘Three types of Ti O2 nanostructures were synthesized via a facile hydrolysis method at195 °C. Effects of the preparation method and doping with N and F on the crystal structure and photocatalytic performance of Ti O2 were investigated. The nanomaterials were characterized by X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, Brunauer–Emmett–Teller porosimetry, ultraviolet–visible diffuse reflectance spectroscopy and fluorescent emission spectra. Their photo-catalytic activity was examined by the photodegradation of methylene blue in aqueous solution under both ultra-violet and visible light irradiation. The results show that nitrogen and fluorine co-doped anatase Ti O2 had the characteristics of a smaller crystalline size, broader light absorption spectrum and lower charge recombination than pure Ti O2. Most importantly, more efficient photocatalytic activity under both ultra-violet and visible light was observed. The obtained N–F-Ti O2 nanomaterial shows considerable potential for water treatment under sunlight irradiation. | Jiemei Yu Zongming Liu Haitao Zhang Taizhong Huang Jitian Han Yihe Zhang Daohuang Chong | 2015 | Journal of Environmental Sciences2015，27，2： | 7 |
| 3 | Occurrence of perfluoroalkyl acids in precipitation from Shenyang,China显示文摘Perfluorosulfonates (PFSAs) and perfluorocarboxylates (PFCAs) in precipitation collected from Shenyang, China were determined. Snow samples were collected in the snow event on March 4, 2007 from 34 sites involving both the urban and suburban areas in Shenyang. The snowmelt was preconcentrated by solid phase extraction and analyzed using LC-MS method. Measurable amounts of perfluoroalkyl acids (PFAS) were found in precipitation samples from Shenyang, demonstrating that wet deposition is one possible pathway for the removing of the selected PFAS chemicals from atmosphere. Major PFAS detected were PFOS (<0.38―51 ng/L), PFOA (0.82―13 ng/L) and PFHpA (0.76―11 ng/L), with their mean concentration of 5.4, 3.3 and 2.9 ng/L, respectively. Other PFSAs and PFCAs were detected at much lower frequency or below the limit of detection in all the samples. The work presented here offers some basis for the investigation on the environmental behavior and the evaluation of human exposure to PFAS. | LIU Wei DONG GuangHui JIN YiHe SASAKI Kazuaki SAITO Norimitsu SATO Itaru TSUDA Shuji NAKAYAMA Shoji F | 2009 | Chinese Science Bulletin2009，54，14： | 6 |
| 4 | Impacts of Drought and Human Activity on Vegetation Growth in the Grain for Green Program Region,China显示文摘The Chinese government adopted six ecological restoration programs to improve its natural environments. Although these programs have proven successful in improving local environments, some studies have questioned their performance when regions suffer from drought. Whether we should consider the effects of drought on vegetation change in assessments of the benefits of ecological restoration programs is unclear. Therefore, taking the Grain for Green Program(GGP) region as a study area, we estimated vegetation growth in the region from 2000–2010 to clarify the trends in vegetation and their driving forces. Results showed that: 1) vegetation growth increased in the GGP region during 2000–2010, with 59.4% of the area showing an increase in the Normalized Difference Vegetation Index(NDVI). This confirmed the benefits of the ecological restoration program. 2) Drought can affect the vegetation change trend, but human activity plays a significant role in altering vegetation growth, and the slight downward trend in the NDVI was not consistent with the severity of the drought. Positive human activity led to increased NDVI in 89.13% of areas. Of these, 22.52% suffered drought, but positive human activity offset the damage in part. 3) Results of this research suggest that appropriate human activity can maximize the benefits of ecological restoration programs and minimize the effects of extreme weather. We therefore recommend incorporating eco-risk assessment and scientific management mechanisms in the design and management of ecosystem restoration programs. | WANG Hao LIU Guohua LI Zongshan YE Xin FU Bojie LV Yihe | 2018 | Chinese Geographical Science2018，28，3： | 6 |
| 5 | Serum levels of perfluorinated compounds in the general population in Shenzhen, China显示文摘Perfluorinated compounds (PFCs) have been detected in many environmental matrices, biota, and nonoccupationally exposed populations in China recently. However, little is known about the distribution and levels of various PFCs in the general population living in areas where there is PFC exposure. In the present study, the levels and prevalence of ten target PFCs were determined in 227 serum samples from a population of nonoccupationally exposed individuals in Shenzhen, China. Results indicated that human exposure to PFCs was prevalent in Shenzhen. Perfluorooctanoate (PFOA) was the dominant PFC contaminant in the serum samples, with a median concentration of 6.72 ng/mL, followed by perfluorooctane sulfonate (PFOS) with a median concentration of 2.07 ng/mL. Other PFCs were detected at much lower concentrations, with median concentrations ranging from 0.02 to 0.87 ng/mL. Statistically, no significant (P>0.05) gender differences were observed for any of the PFCs. Significant (P<0.01) positive correlations were found between age and serum concentrations of the target PFCs, except for perfluorobutane sulfonate (R = 0.16, P = 0.01), perfluorohexanoic acid (R = 0.08, P = 0.22), and perfluoroheptanoic acid (R = 0.11, P = 0.10). Based on the one-compartment pharmacokinetic model, the total daily intakes of PFOA and PFOS for the general population in Shenzhen were calculated as 0.63 and 0.20 ng/kg body weight/day, respectively. | LI Xiao ZHANG JianQing LIU Wei LI XiaoNa ZHANG Xin JIANG YouSheng ZHOU Jian JIN YiHe | 2011 | Chinese Science Bulletin2011，56，28： | 5 |
| 6 | Perfluorooctane sulfonate and perfluorooctanoic acid in the fingernails of urban and rural children显示文摘Perfluorooctane sulfonate(PFOS)and perfluorooctanoic acid(PFOA)are two typical perfluorinated compounds(PFCs),found in a wide range of environmental media and organisms,including humans.Human biomonitoring studies of body fluids have revealed that in many areas of the world the general population has been exposed to background levels of PFOS and PFOA.Fingernail has been suggested as a promising biopsy material for assessment of PFCs environmental exposure.In the present study,PFOS and PFOA were quantified using high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS)in fingernails of urban and rural children(N=93)aged 6-12 years.A questionnaire was conducted to determine factors that could influence the PFOS and PFOA levels in the children.The levels of PFOS in urban children were significantly higher(geometric mean(GM)=328 ng/g)than those in rural children(GM=27 ng/g).In contrast,PFOA levels were significantly lower in the urban children compared with the rural children.Significant positive correlation(R=0.53,P<0.05 for urban areas;R=0.71;P<0.001 for rural areas)between the PFOS and PFOA concentrations indicated they had similar sources.The PFOS and PFOA levels were higher in fingernail samples from children aged <9 years than in children aged ≥9 years.In addition,females had higher PFOA levels than males,in both regions.Other factors that significantly influenced PFOS and PFOA levels were dietary habits and socio-economic background.The results of this study indicate fingernails are a suitable material for biomonitoring of PFCs environmental exposure.However,the levels determined in the fingernail samples need to be first evaluated with regard to the levels determined in other samples,such as human serum. | XU Lei LIU Wei JIN YiHe | 2010 | Chinese Science Bulletin2010，55，33： | 4 |
| 7 | Amorphous red phosphorus anchored on carbon nanotubes as high performance electrodes for lithium ion batteries显示文摘 | Li Sun Yu Zhang Deyang Zhang Jingang Liu Yihe Zhang | 2018 | Nano Research2018，11，5： | 4 |
| 8 | Soil Carbon Stock and Flux in Plantation Forest and Grassland Ecosystems in Loess Plateau, China显示文摘Carbon sequestration occurs when cultivated soils are re-vegetated. In the hilly area of the Loess Plateau, China, black locust(Robinia pseudoacacia) plantation forest and grassland were the two main vegetation types used to mitigate soil and water loss after cultivation abandonment. The purpose of this study was to compare the soil carbon stock and flux of these two types of vegetation which restored for 25 years. The experiment was conducted in Yangjuangou catchment in Yan′an City, Shaanxi Province, China. Two adjacent slopes were chosen for this study. Six sample sites were spaced every 35–45 m from summit to toe slope along the hill slope, and each sample site contained three sampling plots. Soil organic carbon and related physicochemical properties in the surface soil layer(0–10 cm and 10–20 cm) were measured based on soil sampling and laboratory analysis, and the soil carbon dioxide(CO2) emissions and environmental factors were measured in the same sample sites simultaneously. Results indicated that in general, a higher soil carbon stock was found in the black locust plantation forest than that in grassland throughout the hill slope. Meanwhile, significant differences in the soil carbon stock were observed between these two vegetation types in the upper slope at soil depth 0–10 cm and lower slope at soil depth 10–20 cm. The average daily values of the soil CO2 emissions were 1.27 μmol/(m2·s) and 1.39 μmol/(m2·s) for forest and grassland, respectively. The soil carbon flux in forest covered areas was higher in spring and less variation was detected between different seasons, while the highest carbon flux was found in grassland in summer, which was about three times higher than that in autumn and spring. From the carbon sequestration point of view, black locust plantation forest on hill slopes might be better than grassland because of a higher soil carbon stock and lower carbon flux. | HU Chanjuan LIU Guohua FU Bojie CHEN Liding LYU Yihe GUO Lei | 2014 | Chinese Geographical Science2014，24，4： | 2 |
| 9 | Hydrological responses and soil e- rosion potential of abandoned cropland in the Loess Plateau, China 显示文摘 | Liu Yu Fu Bojie Lv Yihe | 2012 | Geomorphology2012，138，1： | 1 |
| 10 | Treatment of heavy oil wastewater by a conventional activated sludge process coupled with an immobilized biological filter显示文摘 | Kun Tong Yihe Zhang Guohua Liu Zhengfang Ye Paul K. Chu | 2013 | International Biodeterioration & Biodegradation2013，，： | 1 |
| 11 | Assessing the soil erosion control service of ecosystems change in the Loess Plateau of China显示文摘 | Fu Bojie Liu Yu Lu Yihe | 2011 | Ecological Complexity2011，8，4： | 1 |
| 12 | A Novel Dual Pointer Approach for Entity Mention Extraction显示文摘The named entity extraction task aims to extract entity mentions from the unstructured text,including names of people, places, institutions and so on. It plays an important role in many Natural language processing(NLP) tasks, such as knowledge bases construction, automatic question answering system and information extraction. Most of the existing entity extraction studies are based on the long text data, which are easier to annotate due to the sufficient contextual information. Extracting entities from short texts such as search queries, conversations is still a challenging task.This paper proposes a dual pointer approach for entity mention extraction, it extracts one entities by two position pointers of the input sentence. The end-to-end deep neural networks model based on the proposed approach can extract the entities by serially generating the dual pointers.The evaluation results on the Chinese public dataset show that the model achieves the state-of-the-art results over the baseline models. | LIU Jie PANG Yihe ZHANG Kai LIU Lizhen YU Zhengtao | 2021 | Chinese Journal of Electronics2021，30，1： | 1 |
| 13 | Interaction of PFOS and BDE-47 co-exposure on thyroid hormone levels and TH-related gene and protein expression in developing rat brains 显示文摘 | WANG Faqi LIU Wei JIN Yihe | 2011 | Toxicol Sci2011，121，2： | 1 |
| 14 | Treatment of heavy oil wastewater by a conventional activated sludge process coupled with an immobilized biologi cal filter显示文摘 | TONG Kun ZHANG Yihe LIU Guohua | 2013 | International Bio-deterioration & Biodegradation2013，84，： | 1 |
| 15 | Assessing the soilerosion control service of ecosystems change in the LoessPlateau of China显示文摘 | Fu Bojie Liu Yu LüYihe | 2011 | Ecological Complexity2011，8，4： | 1 |
| 16 | Pattern analysis in landscape ecology: progress, challenges and outlook 显示文摘 | Chen Liding Liu Yang Lu Yihe | 2008 | stxben2008，28，11： | 1 |
| 17 | Hydrological responses and soil erosion potential of abandoned cropland in the Loess Plateau, China显示文摘 | Yu Liu Bojie Fu Yihe Lü Zhi Wang Guangyao Gao | 2011 | Geomorphology2011，，1： | 1 |
| 18 | Solution growth of NiO nanosheets supported on Ni foam as high-performance electrodes for supercapacitors显示文摘 | Hailong Yan Deyang Zhang Jinyou Xu Yang Lu Yunxin Liu Kangwen Qiu Yihe Zhang Yongsong Luo | 2014 | Nanoscale Research Letters2014，，1： | 1 |
| 19 | Effect of Insufficient Grouting and Strand Corrosion on Flexural Behavior of PCbeams 显示文摘 | Wang Lei Zhang Xuhui Zhang Jianren Ma Yafei Xiang Yihing Liu Yongming | 2014 | Construction and Building Materials2014，53，： | 1 |
| 20 | A novel method for reconstruction in laparoscopic pancreaticoduodenectomy:an experience of 13 cases显示文摘Laparoscopic pancreaticoduodenectomy(LPD)is a challenging operation to general surgeon.Up to date,only about 135 cases have been reported,16 cases in China,119 cases outside China.The reconstruction of alimentary system is a key procedure to ensure success of the whole surgery.It is worth investigating the methods of reconstruc-tion in LPD.A retrospective study is made to investigate the methods of reconstruction in LPD.We analyze 13 cases of LPD performed in our center.Child’s or modified Child’s method was used to make the reconstruction in our practice.We tried three methods to make the anastomosis of pancre-aticojejunostomy,including end-to-end dunking binding pancreaticojejunostomy in two cases,end-to-end dunking pancreaticojejunostomy using interrupted suture in two cases,and duct-to-jejunal end-to-side embedding pancreaticojeju-nostomy in nine cases.The clinical data was collected and analyzed.Three of four patients,who underwent end-to-end pancreaticojejunostomy,had a little pancreatic leakage,especially in the first case.None of other nine patients,who underwent duct-to-jejunal end-to-side embedding pancreati-cojejunostomy,was detected to have pancreatic leakage,and the operating time of these nine cases was less than other four cases.Duct-to-jejunal end-to-side embedding pancreaticoje-junostomy is a safe and efficient method of reconstruction in LPD. | LU Bangyu HUANG Yubin CAI Xiaoyong HUANG Fei LI Jie LU Wenqi XU Jing LIU Zujun YAN Yihe LI Jianjun | 2007 | Frontiers of Medicine2007，1，4： | 1 |
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