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Effects of dietary phosphorous supplementation on laying performance,egg quality,bone health and immune responses of laying hens challenged with Escherichia coli lipopolysaccharide

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Journal of Animal Science and Biotechnology 2018年第4期9卷 980-990页

作者： Wei Nie Bo Wang Jing Gao Yuming Guo Zhong Wang State Key Laboratory of Animal Nutrition College of Animal Science and Technology China Agricultural University Department of Animal Science Washington State University

Background: Phosphorus is an essential nutrient to maintain poultry health and performance. The objective of this study was to evaluate the effect of dietary phosphorus levels on egg production, egg quality, bone health, immune responses of laying hens challenged with Escherichia coli ***: Three hundred laying hens at 28 wk were randomly divided into 2 dietary treatments with 10 replicates of 15 birds. The wheat-soybean based diets contained either 0.12% or 0.4% non-phytate phosphorus(NPP). At 32 wk of age, all the birds of each dietary treatment were injected into the abdomen with 1.5 mg/kg body weight(BW) of either LPS or saline once a day at 24-h intervals for continuous 9 d. The performance of laying hens was evaluated for 9 d. The eggs after the fifth injection were collected to value the egg quality. Three hours after the first injection, blood was collected to measure serum metabolite and immune response associated *** hours after the fifth injection, the hens were euthanized to obtain tibia, cecal tonsils and ***: Compared with saline-injected hens, LPS-injected hens had lower feed intake and egg production(P < 0.05).Eggshell thickness, strength, albumin height and Haugh unit were significantly increased in LPS-injected hens compared with saline-injected hens(P < 0.05). Furthermore, laying hens challenged with LPS had lower villious height/crypt depth ration than those received saline. Serum calcium, phosphorus and SOD activities significantly decreased in the LPS-injected hens compared with the control(P < 0.05). LPS up-regulated expression of IL-1β, IL-6 and IL-10 in cecum, and serum concentration of MDA, IL-1β and IL-6(P < 0.05), whereas 0.40% dietary non-phytate phosphorus supplementation significantly increased(P < 0.05) villi height/crypt depth ratio, decreased(P < 0.05) serum MDA and IFN-γ concentration compared with the 0.12% non-phytate phosphorus ***: In summary, this study demonstrates t

关键词： Egg quality Immune response Laying hens Lipopolysaccharide Phosphorus

Synthesis and optical properties of novel apatite-type NaCa_(3)Bi(PO_(4))_(3)F:Dy^(3+)yellow-emitting fluorophosphate phosphors for white LEDs

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Journal of Rare Earths 2022年第12期40卷 1827-1836,I0001页

作者： Yuan Wang Guangliang Lu Yang Qiu Wen Sun Siqi Qin Yifang Lin Bin Deng Dan zhang Ruijin Yu College of Science Northwest A&F UniversityYangling 712100China School of Chemistry and Environmental Science Xiangnan UniversityChenzhou 423043China Hunan Provincial Key Laboratory of Xiangnan Rare-Precious Metals Compounds Research and Application Xiangnan UniversityChenzhou 423043China College of Chemistry&Pharmacy Northwest A&F UniversityYangling 712100China Key Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion Materials College of Materials and Chemical EngineeringChina Three Gorges UniversityYichang 443002China

In this study,novel yellow-emitting fluorophosphate NaCa_(3)Bi(PO_(4))_(3)F phosphors doped with different concentrations of Dy^(3+)ions were first obtained via high-temperature solid-state *** crystal structure,phase purity,particle morphology,photoluminescence(PL)properties,thermal stability,and luminescence decay curves of the resulting phosphors were then characterized in *** the excitation of 349 nm,the three dominant peaks of the NaCa_(3)Bi(PO_(4))_(3)F:Dy^(3+)are centered at 480 nm(^(4)F_(9/2)-^(6)H_(15/2)),577 nm(^(4)F_(9/2)-^(6)H_(13/2)),and 662 nm(^(4)F_(9/2)-^(6)H_(11/2)).The optimal doping concentration of Dy^(3+)ions in the NaCa_(3)Bi(PO_(4))_(3)F:xDy^(3+)phosphors is x=5 mol%.The phosphors show excellent thermal stability with high activation energy(Ea=0.32 eV).Eventually,the synthesized white lightemitting diode(w-LED)demonstrates the Commission International de L’Eclairage(CIE)chromaticity coordinates of(0.341,0.334),a good correlated color temperature(CCT)of 5083 K,and a high color rendering index(Ra)of *** its potential as yellow-emitting phosphors,the feasibility of the fabricated apatite-type NaCa_(3)Bi(PO_(4))_(3)F:Dy^(3+)fluorophosphate phosphors was confirmed for wLEDs.

关键词： Fluorophosphate NaCa_(3)Bi(PO_(4))_(3)F Dy^(3+) Luminescence Phosphor LEDs

CORRELATION OF SiOx LAYER THICKNESS AND PROPERTIES OF BOPP/SiOx COMPOSITE FILMS WITH SPIN COATING PROCESS PARAMETERS

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chinese Journal of Polymer Science 2013年第2期31卷 333-345页

作者： Xiao-li Yao 马育红 Chang-wen Zhao 杨万泰 Key Laboratory of Carbon Fiber and Functional Polymers Ministry of EducationBeijing University of Chemical Technology State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology

The effects of the spin coating process parameters on the thickness of the SiOx layer of the BOPP/SiOx composite film were investigated. When the concentration of tetraethoxysilane （TEOS） increased from 12.5 vol% to 55% vol%, the SiOx thickness increased from about 80 nm to 470 nm. In the sol time range of 1.5 h to 5 h the SiOx layer thickness reached a maximum at about 4 h and the change of the thickness roughly matched the change of the silica colloidal sphere sizes in sol. When the spin-coating speed of the dispensing stage increased from 450 r/min to 500 r/min, the SiOx layer thickness drastically decreased from about 1.67 gm to 400 nm. While the spin-coating speed of the thinning and drying stage went up to 1200 r/min, the SiOx layer thickness was in the range of 330 nm to 390 nm. It was also found that the SiOx layer thickness was almost increased linearly from about 500 nm to 1.02 gm with the ratio of the commercial silica colloidal to the TEOS from 0.2 to 1.0. The water contact angles decreased to about 23.0° for the BOPP/Si-Sol composite film with 1.67 μm SiOx layer and about 4.0° for the BOPP/mixing Si-Sol composite film with 1.02 μm SiOx layer. Compared to BOPP, the light transparency of the BOPP/Si-Sol composite films decreased by about 5.5% with the SiOx layer from about 80 nm to 1.67 μm and by 7.0% for the BOPP/mixing Si-Sol composite film with the SiOx layer from about 350 nm to 1.02 μm respectively.

关键词： Composites Polypropylene Silicas Spin-coating Hydrophilicity.

Morphology and electrical contact properties of electrical connection materials in corrosive atmosphere

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Rare Metals 2013年第2期32卷 174-178页

作者： Zhi-Gang Kong Liang-Jun Xu Research Laboratory of Electrical Contacts Beijing University of Posts and Telecommunications

The impact mechanism of environmental fac tors, such as corrosive atmosphere, on connector materials was investigated, and the porosity of gold plating was tested. Series of inspections and analytical research meth ods were introduced in this article. The surface morphology of specimens after corrosion was observed by stereoscopic microscope and scanning electron microscope. Chemical constitution was examined by Xray energy spectrum. The contact resistances were measured by fourpoint method. The experiment results show that after exposure to certain environment, the corrosion products, such as Cu20, Cu（NO3）2.3H20, and NiO, are observed on the surface of the specimens without gold coatings, whereas the corrosion products appear to have circleshaped spots on goldplating surface after corrosion test, which indicate that the gold plating has good corrosion protection. The porosity is increased with the increase of corrosion time for every kind of specimens gold plated, and the corrosion degree of gold plating specimens is decreased with the increase of the thickness of gold coatings. The static contact resistances of circleshaped spots appear higher contact resistance than normal value, which can reach to 2,000 mr2 nearly. It is found that the high and unstable contact resistance of the pore and products is more likely to cause contact failure.

关键词： Electrical contact Porosity Corrosion Temperature

Numerical simulation of pedestrian flow past a circular obstruction

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Acta Mechanica Sinica 2011年第2期27卷 215-221页

作者： Yan-Qun Jiang Ru-Xun Liu Ya-Li Duan Department of Mathematics Southwest University of Science and Technology 621010 Mianyang China Department of Mathematics University of Science and Technology of China 230026 Hefei China

In this paper, a revisiting Hughes’ dynamic continuum model is used to investigate and predict the essential macroscopic characteristics of pedestrian flow, such as flow, density and average speed, in a two dimensional continuous walking facility scattered with a circular obstruction. It is assumed that pedestrians prefer to walk a path with the lowest instantaneous travel cost from origin to destination, under the consideration of the current traffic conditions and the tendency to avoid a high-density region and an obstruction. An algorithm for the pedestrian flow model is based on a cellcentered finite volume method for a scalar conservation law equation, a fast sweeping method for an Eikonal-type equation and a second-order TVD Runge-Kutta method for the time integration on unstructured meshes. Numerical results demonstrate the effectiveness of the algorithm. It is verified that density distribution of pedestrian flow is influenced by the position of the obstruction and the path-choice behavior of pedestrians.

关键词： Pedestrian flow · Continuum model ·Finite volume method · Unstructured meshes · Obstruction

Effect of dietary nonphytate phosphorus on laying performance and small intestinal epithelial phosphate transporter expression in Dwarf pink-shell laying hens

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Journal of Animal Science and Biotechnology 2014年第3期5卷 333-339页

作者： Wei Nie Ying Yang Jianmin Yuan Zhong Wang Yuming Guo State Key Laboratory of Animal Nutrition College of Animal Science and TechnologyChina Agricultural University

This study examined the effects of various levels of dietary nonphytate phosphorus on laying performance and the expression patterns of phosphorus metabolism related genes in Dwarf pink-shell Jaying hens. A total of 405 28-week-old Dwarf pink-shell laying hens were fed the same corn-soybean basal meals but containing 0.20%, 0.25%, 0.30%, 0.35% or 0.40% nonphytate phosphorus. The results showed that feed intake, egg production, and average egg weights were quadratically correlated with dietary nonphytate phosphorus content （P 〈 0.05）, and the highest egg production, feed intake and average egg weights were achieved when dietary nonphytate phosphorus was at 0.3% （P 〈 0.05）. mRNA expression of intestinal sodium phosphorus co-transporter linearly decreased when dietary nonphytate phosphorus increased, mRNA and protein expression of intestinal calbindin and vitamin D receptor correlated quadratically with dietary nonphytate phosphorus, and the highest expression was found when dietary available phosphorus was at 0.2,5% to 0.3%. In conclusion, the ideal phosphorus requirement for Dwarf pink-shell layer hens is estimated to be 0.3% in a corn-soybean diet. With this level of phosphorus supplementation, calbindin and vitamin D receptor reached their highest expression.

关键词： Calbindin Laying hens Nonphytate phosphorus Sodium phosphate co-transporter Vitamin D receptor

Detection of maize tassels for UAV remote sensing image with an improved YOLOX Model

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Journal of Integrative Agriculture 2023年第6期22卷 1671-1683页

作者： SONG Chao-yu ZHANG Fan LI Jian-sheng XIE Jin-yi YANG Chen ZHOU Hang ZHANG Jun-xiong College of Engineering China Agricultural UniversityBeijing 100083P.R.China College of Agronomy and Biotechnology China Agricultural UniversityBeijing 100083P.R.China

Maize tassel detection is essential for future agronomic management in maize planting and breeding,with application in yield estimation,growth monitoring,intelligent picking,and disease ***,detecting maize tassels in the field poses prominent challenges as they are often obscured by widespread occlusions and differ in size and morphological color at different growth *** study proposes the SEYOLOX-tiny Model that more accurately and robustly detects maize tassels in the ***,the data acquisition method ensures the balance between the image quality and image acquisition efficiency and obtains maize tassel images from different periods to enrich the dataset by unmanned aerial vehicle(UAV).Moreover,the robust detection network extends YOLOX by embedding an attention mechanism to realize the extraction of critical features and suppressing the noise caused by adverse factors(e.g.,occlusions and overlaps),which could be more suitable and robust for operation in complex natural *** results verify the research hypothesis and show a mean average precision(mAP_(@0.5)) of 95.0%.The mAP_(@0.5),mAP_(@0.5-0.95),mAP_(@0.5-0.95(area=small)),and mAP_(@0.5-0.95(area=medium)) average values increased by 1.5,1.8,5.3,and 1.7%,respectively,compared to the original *** proposed method can effectively meet the precision and robustness requirements of the vision system in maize tassel detection.

关键词： maize tassel detection remote sensing deep learning attention mechanism

Optimization of regenerator based on semiconductor optical amplifier for degraded differential phase shift keying signal

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chinese Physics B 2012年第6期21卷 318-323页

作者：马永欣席丽霞陈光张晓光 State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and Telecommunications

Real time phase regeneration is necessary for degraded phase modulation format optical communication systems. A regenerator based on the discrimitive gain effect of a semiconductor optical amplifier was proposed in recent years. In this paper, for this type of regenerator, its optimal working condition is found by solving the dynamic equations which describe the variance of the optical field and carrier density in the semiconductor optical amplifier by the finite difference method. The results show that the optimal improvement of signal Q factor can reach more than 2.2 dB.

关键词： regenerator semiconductor optical amplifier Q factor improvement phase noise

Security Analysis of a Park-level Agricultural Energy Network Considering Agrometeorology and Energy Meteorology

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CSEE Journal of Power and Energy Systems 2020年第3期6卷 743-748页

作者： Xueqian Fu Dechang Yang Qinglai Guo Hongbin Sun College of Information and Electrical Engineering China Agricultural UniversityChina State Key Laboratory of Power Systems Department of Electrical EngineeringTsinghua UniversityChina

China’s industrial manufacturing industry is well developed,but its agriculture is *** only way to solve this problem is to improve through modern *** cross integration of new energy development and modern agriculture is becoming more and more ***,the research on the interaction between the meteorological disaster of facility agriculture and the power supply security of the integrated energy supply system has not formed a systematic theoretical system,which challenges the collaborative security of the facility agriculture and energy *** this paper,energy meteorology and agrometeorology are considered and modeled,and the static security of a park-level agricultural energy network is simulated and analyzed under different weather conditions.

关键词： Agrometeorology energy network energy meteorology security analysis