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A joint use of emergy evaluation, carbon footprint and economic analysis for sustainability assessment of grain system in China during 2000–2015

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Journal of Integrative Agriculture 2018年第12期17卷 2822-2835页

作者： WANG Xiao-long WANG Wei GUAN Yue-shan xian Yuan-ran HUANG Zhi-xin FENG Hai-yi CHEN Yong College of Agriculture South China Agricultural University

The rapid growth of grain yield in China accelerates a discussion on whether the grain system in China is sustainable. To answer the question, a comprehensive assessment from economic and environmental points is necessary. This study jointly used economic analysis(ECA), emergy evaluation(EME) and carbon footprint(CF) to analyze the environmental and economic sustainability of the grain production system in China based on the national statistical data during 2000–2015. Results showed that the costs of maize, wheat, rice and soybean had increased by 252-346% from 2000 to 2015, causing the lower profit of grain system in recent years. The situation resulted in a serious problem on economic sustainability of grain system in China. Meanwhile, the emergy sustainability index(ESI) of maize, wheat, rice and soybean systems were increasing during 2000–2015, and the CF on unit yield of the crops had been reduced by 10-30% in the study period. The results reflected the improved environmental sustainability of grain system in China during 2000–2015. Nevertheless, the emergy flow of industrial inputs for the crops were increased by 4-22% in the study period, and the CF from the inputs presented a growth rate of 16-23% as well during the same period. The results implied that the grain system in China was relying more on fossil-based inputs. Finally, according to the key points of cost, emergy and CF, we suggest that improving labor efficiency, advanced agricultural practices and optimizing cropping pattern will be effective ways to further improve the economic and environmental sustainability of grain system in China.

关键词： grain sustainability emergy profit carbon footprint time-series

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Determination of the Refractive Index Profile of a Polymer Waveguide by Photobleaching

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Chinese Physics Letters 2000年第6期17卷 433-434页

作者： shan Ji-xiang SHEN Qi-Shun ZHANG ai-Hua CAO Zhuang-Qi CHEN Ying-Li Department of Applied Physics Jiao Tong UniversityShanghai 200030

The shrinkage effect of polymer films,which was demonstrated in our photobleaching experiment,can be fitted approximately by an exponentially decaying *** taking the shrinkage effect into account,the index profile of the polymer waveguide was determined to be a Fermi function with the help of the m-line method and the exact transfer matrix theory.

关键词： function waveguide Waveguide

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Spectrofluorimetric Determination of Magnesium (Ⅱ) with 7-(8-Hydroxy-3, 6-Disulfonaphthylazo)-8-Hydroxyquinoline-5-Sulfonic Acid

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Wuhan University Journal of Natural Sciences 2001年第4期6卷 831-835页

作者： Zhang xian, Wang Hong, Zhang Hua shan College of Chemisitry and Molecular Science, Wuhan University, Wuhan 430072, China Wuhan University College of Chemistry and Molecular Science Wuhan China (GRID:grid.49470.3e) (ISNI:***)

A new fluorescent reagent, 7 (8 hydroxy 3, 6 disulfonaphthylazo) 8 hydroxyquinoline 5 sulfonic acid (HDNHQ) for the determination of magnesium has been developed. It reacted with magnesium to form a 1∶1 fluorescent complex with λ ex / λ em =356/495 nm immediately at room temperature in ammonia ammonium chloride buffer (pH 10.7). A linear relationship was obtained in the magnesium concentration range of 0 160 ng·mL -1 with the detection limit of 0.04 ng·mL -1 . The proposed method was simple, rapid and sensitive. It has been successfully applied to the determination of trace magnesium in blood serum with recoveries of 103.75% and 98.16%, respectively.

关键词： Hydroxy 3 6 disulfonaphthylazo) 8 hydroxyquinoline 5 sulfonic acid magnesium spectrofluorimetry blood serum

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Promising way to address massive intragastric clotting in patients with acute upper gastrointestinal bleeding:A case report

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World Journal of Clinical Cases 2023年第15期11卷 3578-3582页

作者： Su-xian Liu Bei Shi Ya-Feng Liu Jing-Yi shan Bo Sun Department of Gastroenterology Longhua Affiliated Hospital of Shanghai Traditional Chinese MedicineShanghai 210000China

BACKGROUND Massive intragastric clotting(MIC) makes endoscopic therapy difficult in patients with acute upper gastrointestinal bleeding. Literature data on how to address this problem are limited. Here, we report on a case of massive stomach bleeding with MIC that was successfully treated endoscopically using an overtube of singleballoon *** SUMMARY A 62-year-old gentleman with metastatic lung cancer was admitted to the intensive care unit due to tarry stools and hematemesis of 1500 mL of blood during hospitalization. Emergent esophagogastroduodenoscopy revealed massive blood clots and fresh blood in the stomach with evidence of active *** sites could not be observed even by changing the patient’s position and aggressive endoscope suction. The MIC was successfully removed using an overtube connected with a suction pipe, which was inserted into the stomach with an overtube of a single-balloon enteroscope. An ultrathin gastroscope was also introduced through the nose into the stomach to guide the suction. A massive blood clot was successfully removed, and an ulcer with oozing bleeding at the inferior lesser curvature of the upper gastric body was revealed, facilitating endoscopic hemostatic *** This technique appears to be a previously unreported method to suction MIC out of the stomach in patients with acute upper gastrointestinal bleeding. This technique could be considered when other methods are not available or if they fail to remove massive blood clots in the stomach.

关键词： Upper gastrointestinal bleeding Massive intragastric clotting Overtube for single-balloon enteroscope Ultrathin gastroscope Case report

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Single-Atom Protecting Group for on-Surface Synthesis of Graphdiyne Nanowires

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Chinese Journal of Chemical Physics 2019年第5期32卷 620-624页

作者： Huan shan Ya-hui Mao ai-di Zhao Hefei National Laboratory for Physical Sciences at the Microscale Synergetic Innovation Center of Quantum Information & Quantum Physics Department of Chemical Physics University of Science and Technology of China Hefei 230026 China

On-surface synthesis of semiconducting graphdiyne nanowires usually suffer severe side reactions owing to the high reactivity of the butadiynylene units at noble metal surfaces,limiting the production of isolated nanowires. In this work, we report the high-yield synthesis of branchless graphdiyne nanowires [-C≡C-Ph2-C≡C-]nvia on-surface Ullmann coupling of 1,4-bis（4-bromophenyl）-1,3-butadiyne molecules with chemical vapor deposition ***-contact atomic force microscopy with single-bond resolution reveals that single gold adatoms act as effective protecting groups for butadiynylene units by forming Au-π ligand bonds, preventing unwanted branched coupling reactions and enabling the synthesis of ultralong isolated graphdiyne nanowires. This study will stimulate further investigation on the role of various surface adatoms in protecting on-surface reactions.

关键词： On-surface synthesis Graphdiyne Ullmann coupling Protecting group Atomic force microscopy

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The mechanisms through which auricular vagus nerve stimulation protects against cerebral ischemia/reperfusion injury

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Neural Regeneration Research 2022年第3期17卷 594-600页

作者： Jing-Jun Zhao Zheng-Hui Wang Ying-Jie Zhang Wen-Jing Wang ai-Fang Cheng Pei-Jing Rong Chun-Lei shan Center of Rehabilitation Medicine Yueyang Hospital of Integrated Traditional Chinese and Western MedicineShanghai University of Traditional Chinese MedicineShanghaiChina School of Rehabilitation Science Shanghai University of Traditional Chinese MedicineShanghaiChina Engineering Research Center of Traditional Chinese Medicine Intelligent Rehabilitation Ministry of EducationShanghaiChina Center of Rehabilitation Medicine the First Affiliated Hospital of Xinxiang Medical UniversityXinxiangHenan ProvinceChina shanghai Research Institute of Acupuncture and Meridian ShanghaiChina Institute of Acupuncture and Moxibustion Chinese Academy of Chinese Medical SciencesBeijingChina

Previous studies have shown that vagus nerve stimulation can improve patients' locomotor *** stimulation of the auricular vagus nerve,which is the only superficial branch of the vagus nerve,may have similar effects to vagus nerve ***,the precise mechanisms remain poorly *** this study,rat models of cerebral ischemia/reperfusion injury were established by modified Longa ***-four hours later,7-day auricular vagus nerve stimulation was *** results showed that auricular vagus nerve stimulation promoted the secretion of acetylcholine,inhibited the secretion of interleukin-1β,interleukin-6,and tumor necrosis factor-α,and reduced connexin 43 phosphorylation in the ischemic penumbra and motor cortex,promoting locomotor function recovery in rats with cerebral ischemia/reperfusion *** findings suggested that auricular vagus nerve stimulation promotes the recovery of locomotor function in rats with cerebral ischemia/reperfusion injury by altering the secretion of acetylcholine and inflammatory factors and the phosphorylation of connexin *** study was approved by the Animal Use and Management Committee of shanghai University of Traditional Chinese Medicine on November 8,2019(approval ***191108014).

关键词： auricular vagus nerve stimulation connexin 43 gap junction inflammatory factor ischemia/reperfusion injury neurological function neuroprotection stroke

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Balancing free and confined metallic Ni for an active and stable catalyst——A case study of CO methanation over Ni/Ni–Al2O3

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Journal of Energy Chemistry 2020年第11期29卷 73-84页

作者： Yong-shan Xiao Yong-Hong Song Chang Liu xian-Ying Shi Han-Qing Ge Min-Li Zhu Zhao-Tie Liu Zhong-Wen Liu Key Laboratory of Syngas Conversion of Shaanxi Province School of Chemistry&Chemical EngineeringShaanxi Normal UniversityXi'an 710119ShaanxiChina

We propose a new strategy to make an active and stable Ni-based catalyst which can be operated in a wide range of reaction temperatures. The ordered mesoporous alumina(OMA) with confined Ni in the pore wall(Ni-OMA) was prepared via the one-pot evaporation induced self-assembly method. By using the incipient impregnation method, different amounts of free Ni were loaded over Ni-OMA(Ni/NiOMA) at a fixed total NiO content of 15 wt%. Characterization results confirmed the formation of wellstructured Ni-OMA, and the ordered structure was still well preserved even after impregnating NiO at a content of as high as 12 wt%. The catalysts were evaluated for the CO methanation as a model reaction under varied conditions. Importantly, the activity and stability of Ni/Ni-OMA for the titled reaction were significantly regulated by simply changing the ratio of the confined to free Ni. Over the optimum catalyst of NiO(2 wt%)/NiO(13 wt%)-OMA, the high activity at a temperature of as low as 300 ℃ was achieved with the space-time yield of methane over 7.6 g gcat-1 h-1 while a long-term stability for a time-onstream of 400 h was confirmed without an observable deactivation under the conditions of 600 ℃ and an extremely high gas hourly space velocity of 120,000 mL g-1 h-1. The results were well explained as the integrated merits of the free Ni for a high dispersion and the confined Ni in OMA for the anti-sintering property.

关键词： CO methanation Ni Ordered mesoporous alumina Evaporation induced self-assembly Ni-support interactions

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Discoursing on Soxhlet extraction of ginseng using association analysis and scanning electron microscopy

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Journal of Pharmaceutical Analysis 2018年第5期8卷 312-317页

作者： Yuan Yue Zi-Dong Qiu xian-You Qu ai-Ping Deng Yuan Yuan Lu-Qi Huang Chang-Jiang-Sheng Lai Chongqing Academy of Chinese Materia Medica Chongqing Key Laboratory of Traditional Chinese Medicine ResourcesChongqing Sub-center of National Resource Center for Chinese Materia MedicaChina Academy of Chinese Medical SciencesChongqing 400065PR China National Resource Center for Chinese Materia Medica China Academy of Chinese Medical SciencesState Key Laboratory Breeding Base of Dao-di HerbsBeijing 100700PR China State Key Laboratory of Natural Medicines(China Pharmaceutical University) No.24 Tongjia laneNanjing 210009PR China

Soxhlet extraction is a common method of sample preparation. However, there has been no discussion about the efficiency of Soxhlet extraction from different batches and the factors that cause content fluctuation. In this study, Panax ginseng was selected as a model sample. Soxhlet extraction by means of a water bath, which has always been neglected, was identified as a novel key factor in the poor repeat- ability in different batches of Soxhlet extraction, as it can affect the siphon times and reflux time, which have been positively correlated with the ginsenoside contents. By substituting round bottom flasks in the same column, the relative standard deviation of the most fluctuated compound, ginsenoside Rbl, was decreased from 24.6% to 5.02%. Scanning electron microscopy analysis confirmed that the breakdown of the surface of the ginseng powder in the Soxhlet extraction led to a better dissolution of ginsenosides, indicating that chloroform may promote the extraction of ginsenosides by disrupting the cell structure. Moreover, 70% methanol was regarded as the better solvent for extracting the ginsenosides. Overall, this work offers a practical and effective protocol for improving the accuracy and repeatability of Soxhlet extraction methodology for ginsenosides and other analytes.

关键词： Ginseng Ginsenosides Soxhlet extraction Repeatability Siphon times

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High cycle rotating bending fatigue performance and fracture behavior in a pearlite-ferrite dual-phase steel

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Journal of Iron and Steel Research International 2022年第3期29卷 519-528页

作者： Xin-bo Ji Si-xin Zhao Li-ming Fu Jian Peng Jia-qiang Gao Da-jiang Yu Zong-ze Huang ai-dang shan School of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai200240China Baosteel Research Institute Baoshan Iron and Steel Co.Ltd.Shanghai201900China

To clarify the effects of ferrite morphologies and contents on high-cycle fatigue property of pearlite-ferrite dual-phase(DP)steel used for fabrication of commercial vehicle crankshafts,two types of DP steels with different ferrite grain sizes(S10:13.1μm and S30:21.4μm)and ferrite contents(S10:~9.5 vol.%and S30:~30.4 vol.%)were *** amplitude-logarithm of number of high cycles to failure fatigue of the two DP steels was *** results showed a fatigue strength of 510 and 400 MPa for S10 and S30 steels,respectively,at 10^(7) *** cracks in S10 steel extended preferentially along the grain boundary,but it was easy for crack propagation to extend within a pearlite colony to form a zigzag crack *** roughness was enhanced and high stress was introduced to the crack surface due to this kind of crack propagation behavior,which has positive effects on slowing down crack ***,the crack propagation in S30 steel mainly occurred inside the soft equiaxed coarse ferrite *** revealed that little stress was introduced to the crack *** results show that it is possible to improve high cycle fatigue strength of pearlite-ferrite DP steel by appropriately manipulating the volume fraction and microstructure morphology of ferrite phase.

关键词： Pearlite-ferrite steel Ferrite morphology Ferrite content Fatigue perfomance Fracture characteristics

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High-sensitivity phase imaging eddy current magneto-optical system for carbon fiber reinforced polymers detection

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Journal of Electronic Science and Technology 2023年第4期21卷 48-59页

作者： Jiang-shan ai Quan Zhou Yi-Ping Liang Chun-Rui Feng Bing Long Li-Bing Bai Yong-Gang Wang Chao Ren School of Automation Engineering University of Electronic Science and Technology of ChinaChengdu611731China Department of Mechanical Engineering Catholic University of LeuvenLeuven3001Belgium Chengdu aircraft Industry Company Ltd. Chengdu610091China

This paper proposed a high-sensitivity phase imaging eddy current magneto-optical (PI-ECMO) system for carbon fiber reinforced polymer (CFRP) defect detection. In contrast to other eddy current-based detection systems, the proposed system employs a fixed position excitation coil while enabling the detection point to move within the detection region. This configuration effectively mitigates the interference caused by the lift-off effect, which is commonly observed in systems with moving excitation coils. Correspondingly, the relationship between the defect characteristics (orientation and position) and the surface vertical magnetic field distribution (amplitude and phase) is studied in detail by theoretical analysis and numerical simulations. Experiments conducted on woven CFRP plates demonstrate that the designed PI-ECMO system is capable of effectively detecting both surface and internal cracks, as well as impact defects. The excitation current is significantly reduced compared with traditional eddy current magneto-optical (ECMO) systems.

关键词： Carbon fiber reinforced polymers Defect detection Eddy current magneto-optical Nondestructive testing Phase imaging

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