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Variation characteristic of drilling force and influence of cutting parameter of SiCp/Al composite thin-walled workpiece

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Advances in Manufacturing 2019年第3期7卷 288-302页

作者： Shu-Tao Huang Chao Li Li-Fu Xu lin Guo xiao-lin yu School of Automobile and Traffic Shenyang Ligong UniversityShenyang 110159People's Republic of China School of Mechanical Engineering Dalian University of TechnologyDalian 116024LiaoningPeople's Republic of China School of Mechanical Engineering Shenyang Ligong UniversityShenyang 110159People's Republic of China

In this paper,the variation characteristic of the drilling force,and the influences of cutting speed,feed rate,and workpiece thickness on the drilling force,were eval・uated when drilling a silicon carbide particle reinforced aluminum matrix(SiCp/Al)composite thin-walled workpiece with a high volume *** the condition that the workpiece thickness was less than the drill tip height,three characteristic stages of drilling force variation were *** results indicate that there is a sign币cant difference between the variations in the drilling force when drilling a thin-walled workpiece compared to thick-walled *** the chisel edge drills out the lower surface of the workpiece,there is an abrupt decrease in the thrust forces of the thin-walled and thick-walled *** addition,there is an abrupt decrease in the torque of the thick-walled workpiece,whereas that of the thinwalled workpiece *** to the thickness of the thin-walled workpiece,the instant of the abrupt decrease in the thrust force may lead or lag behind the theoretical instant at which the chisel edge reaches the lower surface of the workpiece without *** drilling a thin-walled hole,the cutting speed has a slight influence on the thrust force,and there is a slight increase in the torque in accordance with an increase in the cutting *** thrust force and torque increase in accordance with an increase in the feed *** drilling a thinwalled workpiece with a thickness of 1 mm,the critical thickness of workpiece cracking decreases in accordance with an increase in the cutting speed,and increases in accordance with an increase in the feed *** drilling a thin-walled workpiece with a thickness of 0.5 mm,the concave deformation of the workpiece and the critical thickness of the workpiece cracking increase in accordance with an increase in the feed ***,the increment in the critical thickness of the workpiece cracking is less than that in

关键词： SiCp/Al composites Thin-walled workpiece Drilling Drilling force

Significant reduction of ammonia emissions while increasing crop yields using the 4R nutrient stewardship in an intensive cropping system

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Journal of Integrative Agriculture 2023年第6期22卷 1883-1895页

作者： ZHANG Chong WANG Dan-dan ZHAO Yong-jian xiao yu-lin CHEN Huan-xuan LIU He-pu FENG Li-yuan yu Chang-hao JU xiao-tang College of Tropical Crops Hainan UniversityHaikou 570228P.R.China College of Resources and Environmental Sciences China Agricultural UniversityBeijing 100193P.R.China

Ammonia (NH_3) emissions should be mitigated to improve environmental *** are one of the largest NH_3sources,they must be managed properly to reduce their emissions while achieving the target ***,we report the NH_3 emissions,crop yield and changes in soil fertility in a long-term trial with various fertilization regimes,to explore whether NH_3 emissions can be significantly reduced using the 4R nutrient stewardship (4Rs),and its interaction with the organic amendments (i.e.,manure and straw) in a wheat–maize *** the 4Rs significantly reduced NH_3 emissions to 6 kg N ha~(–1) yr~(–1) and the emission factor to 1.72%,without compromising grain yield (12.37 Mg ha~(–1) yr~(–1))and soil fertility (soil organic carbon of 7.58 g kg~(–1)) compared to the conventional chemical N *** using the 4R plus manure,NH_3 emissions (7 kg N ha~(–1) yr~(–1)) and the emission factor (1.74%) were as low as 4Rs,and grain yield and soil organic carbon increased to 14.79 Mg ha~(–1) yr~(–1) and 10.09 g kg~(–1),*** manure substitution not only significantly reduced NH_3 emissions but also increased crop yields and improved soil fertility,compared to conventional chemical N *** return exerted a minor effect on NH_3 *** results highlight that 4R plus manure,which couples nitrogen and carbon management can help achieve both high yields and low environmental costs.

关键词： ammonia emission crop yield 4R nutrient stewardship partial manure substitution winter wheat–summer maize cropping system

Clinical value of predictive models based on liver stiffness measurement in predicting liver reserve function of compensated chronic liver disease

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World Journal of Gastroenterology 2022年第42期28卷 6045-6055页

作者： Rui-Min Lai Miao-Miao Wang xiao-yu lin Qi Zheng Jing Chen Department of Hepatology Hepatology Research InstituteThe First Affiliated HospitalFujian Medical UniversityFuzhou 350005Fujian ProvinceChina Department of Endocrinology The 910th Hospital of The Joint Service Support ForceQuanzhou 362000Fujian ProvinceChina

BACKGROUND Assessment of liver reserve function(LRF)is essential for predicting the prognosis of patients with chronic liver disease(CLD)and determines the extent of liver resection in patients with hepatocellular *** To establish noninvasive models for LRF assessment based on liver stiffness measurement(LSM)and to evaluate their clinical *** A total of 360 patients with compensated CLD were retrospectively analyzed as the training *** new predictive models were established through logistic regression analysis and were validated internally in a prospective cohort(132 patients).RESULTS Our study defined indocyanine green retention rate at 15 min(ICGR15)≥10%as mildly impaired LRF and ICGR15≥20%as severely impaired *** constructed predictive models of LRF,named the mLPaM and sLPaM,which involved only LSM,prothrombin time international normalized ratio to albumin ratio(PTAR),age and model for end-stage liver disease(MELD).The area under the curve of the mLPaM model(0.855,0.872,respectively)and sLPaM model(0.869,0.876,respectively)were higher than that of the methods for MELD,albumin bilirubin grade and PTAR in the two cohorts,and their sensitivity and negative predictive value were the highest among these methods in the training *** addition,the new models showed good sensitivity and accuracy for the diagnosis of LRF impairment in the validation *** The new models had a good predictive performance for LRF and could replace the indocyanine green(ICG)clearance test,especially in patients who are unable to undergo ICG testing.

关键词： Liver stiffness measurement Chronic liver disease Liver reserve function Indocyanine green clearance test Predictive model

Improvement of the Injection and Transport Characteristics of Electrons in Organic Light-Emitting Diodes by Utilizing a NaC1 N-Doped Layer

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Chinese Physics Letters 2014年第4期31卷 178-181页

作者： xiao Zhi-Hui WU xiao-Ming HUA yu-lin WANG Li BI Wen-Tao BAI Juan-Juan MU Xue YIN Shou-Gen School of Materials Science and Engineering Tianjin University of Technology Tianjin 300384Key Laboratory of Display Materials and Photoelectric Devices .Ministry of Education Tianjin 300384 Tianjin Key Laboratory of Photoelectric Materials and Devices Tianjin 300384

The injection and transport characteristics of electrons are enhanced by using sodium chloride （NaC1） as an n-type dopant doped into a 4, 7-diphnenyl-1, lO-phe-nanthroline （Bphen） electron-transporting layer, which improves the performance of organic light-emitting diodes （OLEDs）. Meanwhile, a NaCl-doped Bphen layer can effectively influence electrical characteristics of the devices, and significantly improve the current and power efficiency. The turn-on voltage and the operation voltage of the optimal device are decreased drastically from 6.5 V and 10.8 V to 3.3 V and 5 V, respectively, compared with those of the reference device. The maximum current efficiency and power efficiency of the optimal device are 7.0 cd/A and 4.4 Im/W at the current density of 16.70 mA/cm~, which are about I. 7 and 4 times higher than those of the reference device, respectively. Moreover, the enhancement of the injection and transport ability for electrons is attributed not only to the reduced energy barrier between A1 cathode and Bphen, but also to the increased mobility of electrons by the doping effect of NaCl. Therefore, both the electron injection and transport ability are enhanced, which improve the carrier balance in OLEDs and lead to the better device efficiency.

关键词： ORGANIC light emitting diodes SALT DOPING agents (Chemistry) ENERGY consumption ELECTRON mobility

Sepaktakraw-like catalyst Mn-doped CoP enabling ultrastable electrocatalytic oxygen evolution at 100 mA·cm^(-2) in alkali media

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Rare Metals 2022年第9期41卷 3069-3077页

作者： Wen-Ying Fu yu-xiao lin Mao-Sen Wang Si Si Lu Wei Xin-Sheng Zhao Yong-Sheng Wei School of Physics and Electronic Engineering Jiangsu Normal UniversityXuzhou221116China School of Mechatronic Engineering China University of Mining and TechnologyXuzhou221116China

Seeking highly active,stable and low-cost electrocatalysts used as both cathode and anode in overall water splitting is very crucial for the sustainable utilization of ***,a highly efficient and long-term stable oxygen evolution reaction(OER)electrocatalyst Mn-doped CoP on foam Ni(MnCoP/NF)is synthesized by the one-step electrodeposition *** to the synergetic effect among the Sepaktakraw-like morphology,the doped Mn element and the binder-free synthesis method,MnCoP/NF displays superior electrocatalytic activity and electrochemical stability toward ***/NF only requires an overpotential of 266 mV to deliver the current density of 10 mA·cm^(-2),demonstrating an excellent electrocatalytic activity even better than that of commercial catalysts of IrO_(2)/*** the retention rate of potential can still be maintained at 99.57%after the durability test as long as 240 h,indicating the prominent electrochemical stability of MnCoP/***,MnCoP/NF could be directly used as both cathode and anode in the two-electrode system for overall water splitting,exhibiting a low potential of 1.97 V for reaching 100 mA·cm^(-2).Impressive long-term stability of MnCoP/NF is also observed by limited activity decay after 240-h durability tests at 10 and 100 mA·cm^(-2).Thus,this study illustrates a feasible approach to the rational design of highly active and stable electrocatalyst and also provides valuable insights on the improved electrocatalytic performance of water splitting by Mn doping.

关键词： Electrocatalysts Overall water splitting MnCoP/NF Electrodeposition

Effect of the Antisense BcMF12 Driven by the BcA9 Promoter on Gene Silencing in Brassica campestris ***

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Agricultural Sciences in China 2008年第8期7卷 922-928页

作者： SONG Jiang-hua ZHANG Li-xin yu xiao-lin CAO Jia-shu The Institute of Vegetable Science Zhejiang University Hangzhou 310029 P.R.China College of Horticulture Anhui Agricultural University Hefei 230036 P.R. China College of Plant Protection Anhui Agricultural University Hefei 230036 P.R. China

The study analyzed the silencing of BcMF12 gene regulated by BcA9 promoter in the transgenic pakchoi and confirmed the effect of antisense BcMF12 gene on the pollen development. A conserved BcMF12 gene fragment was amplified from the cDNA of flower buds in pakchoi （Brassica campestris L. ssp. chinensis, syn. B. rapa L. ssp. chinensis） and was fused to the anther specific BcA9 promoter. The plant antisense expression vector was constructed and then introduced into pakchoi via Agrobacterium-mediated transformation. The transgenic plants were screened by antibiotics and molecular analysis. PCR and Southern blot revealed that the antisense BcMF12-GUS fusion gene regulated by BcA9 promoter was integrated into transgenic plants. Northern blot suggested that the expression of BcMF12 gene was down-regulated significantly. The pollen germination rate of transgenic plants with antisense BcMF12 gene decreased as compared with that of the control plants. The expression of the gene BcMF12 related to the pollen development was inhibited by the antisense BcMF12 driven by BcA9 promoter, which consequently affected the pollen development in pakchoi.

关键词： Brassica campestris L. ssp. chinensis BcMF12 BcA9 promoter antisense RNA gene expression GUSactivity

Preparation of （2E）-3-（4＇-Halophenyl）prop-2-enoyl Sulfachlorpyridazine Sodium Salts and Their Interaction with Bovine Serum Albumin by Fluorescence Spectroscopy

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Chemical Research in Chinese Universities 2013年第5期29卷 854-860页

作者： DU Chuan-rong LUO Xuan WEI Jin-rui HE Ting-ting ZHENG xiao-yu lin Cui-wu School of Chemistry and Chemical Engineering Guangxi University Nanning 530004 P. R. China

Three （2E）-3-（4＇-halophenyl）prop-2-enoyl sulfachlorpyridazine sodium salts（XPSCA） were synthesized. Their chemical structures were confirmed by IH NMR and 13C NMR, electrospray ionization mass spectrometry （ESI-MS）, and infrared（IR） spectroscopy. The interactions between XPSCA and bovine serum albumin（BSA） were investigated under imitated physiological condition by fluorescence quenching technique and UV-Vis absorption spectroscopy according to the Stern-Volmer equation. The results from the emission quenching at different tempera- tures indicate that the quenching mechanism of serum albumin by XPSCA was static quenching mechanism at low XPSCA concentrations or a combined quenching（static and dynamic） mechanism at higher XPSCA concentrations. At different temperatures, the binding constant and the binding sites of XPSCA with BSA were investigated, and the distances were evaluated according to F6rster non-radiative resonance energy transfer theory. The thermodynamic parameters were calculated according to van＇t Hoff equation, which implies that both van der Waals interaction and hydrogen bond played major roles in stabilizing the XPSCA-BSA complexes, whereas hydrophobic interactions were secondary. Moreover, the conformational changes in BSA were analyzed by synchronous fluorescence spectra.

关键词： Sulfachlorpyridazine sodium Bovine serum albumin Halo-cinnamic acid Fluorescence spectroscopy

Discussion of Optimal Allocation of Resources Theory for Communication Enterprises

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The Journal of China Universities of Posts and Telecommunications 2004年第z1期11卷 103-106页

作者： JIN xiao-lin yu Hua SU Hua-ying Beijing University of Posts and Telecommunications Beijing 100876P.R.China. Beijing University of Posts and Telecommunications Beijing 100876P.R.China. Beijing University of Posts and Telecommunications Beijing 100876P.R.China.

The theory on the resource optimal allocation is discussed in this article. On the base of the discussion, for the main problems existing in the resource allocation of communication enterprises, the reasonable allocat... 详细信息

关键词： resource allocation marginal theory communication enterprise

The ‘Two oceans and one sea' extended range numerical prediction system with an ultra-high resolution atmosphere-ocean-land regional coupled model

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Atmospheric and Oceanic Science Letters 2018年第4期11卷 364-371页

作者： Zhang Shao-Qing Yang LIU Ma xiao-Hui Wang Hong-Na Zhang Xue-Feng yu xiao-lin Lu Lv Physical Oceanography Laboratory/CIMST Ocean University of China & National Laboratory for Marine Science and Technology Key Laboratory of Research on Marine Hazard Forecasting National Marine Environmental Forecasting Center Ministry of Natural Resources of the People's Republic of China Institute of Oceanology Chinese Academy of Sciences & National Laboratory for Marine Science and Technology National Marine Information Center Ministry of Natural Resources of the People's Republic of China College of Ocean and Atmosphere Ocean University of China

The‘Two Oceans and One Sea’area(West Pacific,Indian Ocean,and South China Sea;15°S–60°N,39°–178°E)is a core strategic area for the‘21st Century Maritime Silk Road’project,as well as national *** the increasing demand for disaster prevention and mitigation,the importance of 10–30-day extended range prediction,between the conventional short-term(around seven days)and the climate scale(longer than one month),is ***,marine extended range prediction is still a‘blank point’in China,making the early warning of marine disasters almost ***,the authors introduce a recently launched Chinese national project on a numerical forecasting system for extended range prediction in the‘Two Oceans and One Sea’area based on a regional ultra-high resolution multi-layer coupled model,including the scientific aims,technical scheme,innovation,and expected *** completion of this prediction system is of considerable significance for the economic development and national security of China.

关键词： Numerical prediction system ultra-high resolution multi-layer coupled model extended range prediction