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Release Characteristics of Different N Forms in an Uncoated Slow/Controlled Release Compound Fertilizer

Agricultural Sciences in China 2007年第3期6卷 330-337页

作者： dong yan wang Zheng-yin College of Resources and Environmental Sciences Southwest University Chongqing 400716 P.R.China

This study examined the release characteristics of different N forms in an uncoated slow/controlled-release compound fertilizer （UCRF） and the N uptake and N-use efficiency by rice plants. Water dissolution, soil leaching, and pot experiments were employed. The dynamics of N release from the UCRF could be quantitatively described by three equations： the first-order kinetics equation [N1=N0 （1-e^-kt）], Elovich equation （N1=a ＋ blnt）, and parabola equation （N1=a ＋ bt^0.5）, with the best fitting by the first-order kinetics equation for different N （r= 0.9569^＊＊-0.9999^＊＊）. The release potentials （No values estimated by the first-order kinetics equation） of different N in the UCRF decreased in the order of total N 〉 DON 〉 urea-N 〉 NH4^＋-N 〉 NO3^-N in water, and total N 〉 NH4^＋-N 〉 DON 〉 urea-N 〉 NO3^--N in soil, respectively, being in accordance with cumulative amounts of N release. The constants of N release rate （k values and b values） for different N forms were in decreasing order of total N 〉 DON 〉 NH4^＋-N 〉 NO3^--N in water, whereas the k values were urea- N 〉DON 〉 NH4^＋-N 〉 total N 〉 NO3^--N, and the b values were total N 〉 NH4^＋-N 〉 DON 〉 NO3^--N 〉 urea-N in soil. Compared with a common compound fertilizer, the N-use efficiency, N-agronomy efficiency, and N-physiological efficiency of the UCRF were increased by 11.4%, 8.32 kg kg^-1, and 5.17 kg kg^-1, respectively. The ratios of different N to total N in the UCRF showed significant correlation with N uptake by rice plants. The findings showed that the first-order kinetics equation [Nt=N0 （l-e^kt）] could be used to describe the release characteristics of different N forms in the fertilizer. The UCRF containing different N forms was more effective in facilitating N uptake by rice compared with the common compound fertilizer containing single urea-N form.

关键词： slow/controlled release compound fertilizer nitrogen forms release kinetics nitrogen use efficiency

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Deformation-induced martensitic transformation kinetics and correlative micromechanical behavior of medium-Mn transformation-induced plasticity steel

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Journal of Materials Science & Technology 2019年第8期35卷 1779-1786页

作者： Minghe Zhang Haiyang Chen Youkang wang Shengjie wang Runguang Li Shilei Li yan-dong wang Beijing Advanced Innovation Center for Materials Genome Engineering State Key Laboratory for Advanced Metals and MaterialsUniversity of Science and Technology Beijing

An in situ high-energy X-ray diffraction(HE-XRD) technique was mainly used to investigate the micromechanical behavior of medium-Mn Fe-0.12 C-10.16 Mn-1.87 Al(in wt%) transformation-induced plasticit(TRIP) steel subjected to intercritical annealing at 625℃, 650℃, 675℃ and 700℃ for 1 h. As the intercritical annealing temperature increased, the volume fraction of retained austenite(RA) and ultimate tensilstress(UTS) increased, while the Lüders strain and yield stress(YS) decreased. The incremental workhardening exponent of experimental steel increased with increasing intercritical annealing temperatureThe overall trend of the transformation kinetics of the RA with respect to the true strain followed thsigmoidal shape predicted by the Olson and Cohen(OC) model. Load partitioning occurred among the ferrite, austenite and martensite immediately after entering the yielding stage. Because the stability of thRA decreased with increasing intercritical annealing temperature, the load undertaken by the martensitincreased. The moderate transformation kinetics of the RA and effective load partitioning among constituent phases were found to contribute to a favorable combination of strength and ductility for thimedium-Mn TRIP steel.

关键词： Medium-Mn TRIP steel High-energy X-ray diffraction Transformation kinetics Load partitioning

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Capacity of FH wireless multi-hop networks

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The Journal of China Universities of Posts and Telecommunications 2009年第6期16卷 78-83页

作者： WEI dong-yan wang Wen-bo PENG Mu-gen Key Laboratory of Universal Wireless Communication Ministry of Education Beij hag University of Posts and Telecommunications Beijing 100876 China

In this article,the capacity of wireless multi-hop networks with the frequency hopping（FH） technique is *** from the previous work based on non-spread spectrum（SS） system,this study is based on frequency hopping spread spectrum（FHSS） and the retransmission *** analysis results show that the normalized transport capacity decreases as 1/Mλ,when the total available frequency band is divided into M sub-bands for frequency hopping and the nodes are randomly distributed in space according to a Poisson point process with intensity λ .In this work,the best transmission range per hop to get the maximum capacity is also ***,the results summarize how the capacity of FH wireless multihop networks is affected by the outage probability,target signal to interference plus noise ratio（SINR） and other system parameters.

关键词： multihop frequency hopping capacity

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Effectiveness of hot deformation and subsequent annealing forβgrain refinement of Ti-5Al-5Mo-5V-1Cr-1Fe titanium alloy

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Rare Metals 2021年第12期40卷 3608-3615页

作者： Yi-Min Cui Wei-Wei Zheng Chao-Hua Li Guan-Hua Cao yan-dong wang State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China

High strength titanium alloys suffer from a limited combination of strength and *** their micro structure,the coarseβgrain is a detrimental *** the present study,the effects of hot deformation and annealing treatment on theβgrain refinement of Ti-5 Al-5 Mo-5 V-1 Cr-1 Fe(TC18)titanium alloy have been investigated by using electronic backscattered diffraction(EBSD)and transmission electric microscopy(TEM).Hot compression tests of TC18 alloy were performed between 1073 and 1223 K at strain rates of 0.01 and 0.10 s^(-1)·Subsequent annealing treatments were conducted to investigate the effect of deformation microstructure on the recrystallization behavior ofβ*** results indicate that dynamic recovery(DRV)is the dominant restoration mechanism during hot *** dynamic recrystallization(dDRX)is significantly limited at a higher temperature in theβregion,whereas continuous dynamic recrystallization(cDRX)of theβphase is observed at a higher strain rate in the(α+β)*** final annealing microstructure is highly dependent on the deformation *** dDRX during hot deformation could not effectively refine theβ*** refined and uniformβgrains with an average grain size of 12μm are achieved by combining hot deformation and subsequent annealing in the(α+β)*** study provides a guide for theβgrain refinement of high strength titanium alloys.

关键词： Grain refinement Dynamic recrystallization Hot deformation High strength titanium alloy

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Mesoscale Simulation for Polymer Migration in Confined Uniform Shear Flow

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Chemical Research in Chinese Universities 2010年第1期26卷 122-127页

作者： HE yan-dong wang Yong-lei LU Zhong-yuan LI Ze-sheng State Key Laboratory of Theretical and Computational Chemistry Institute of Theoretical Chemistry Jilin University Changehun 130021P. R. China

The structure and dynamics of confined single polymer chain in a dilute solution, either in equilibrium or at different shear rates in the uniform shear flow fields, were investigated by means of dissipative particle dynamics simulations. The no-slip boundary condition without density fluctuation near the wall was taken into account to mimic the environment of a nanochannel. The dependences of the radius of gyration, especially in three different di- rections, and the density profile of the chain mass center on the strength of the confinement and the Weissenberg number（Wn） was studied. The effect of the interaction between polymer and solvent on the density profile was also investigated in the cases of moderate and strong Wn. In the high shear flow, the polymer migrates to the center of the channel with increasing Wn. There is only one density profile peak in the channel center in the uniform shear flow, which is in agreement with the results of the experiments and theory.

关键词： Confined polymer Dissipative particle dynamics No-slip boundary condition Uniform shear flow

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Temperature-triggered phase transition in pyridazine hexafluorophosphate

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Chinese Chemical Letters 2015年第1期26卷 145-148页

作者： dong-yan wang Li-Li Qin Xue-Li Hou Heng-Yun Ye Ordered Matter Science Research Center Southeast University

The pyndazine hexafluorophosphate[C4H5N2]~＋[PF6]^-（1） undergoes a reversible phase transition around140 K,which was confirmed by the DSC measurement.Variable-temperature crystal structures determined at 293 K and 93 K show that the compound crystallizes in the same space group P21/c,indicating that 1 undergoes an iso-structural phase *** the temperature decreases,dielectric measurement of the title compound shows no significant change around the phase transition *** hydrogen bonds are found between molecules at 293 K and 93 l〈 with similar packing *** most distinct difference between the low temperature and room temperature structures is the order-disorder transition of the hexafluorophosphate anion,which is probably the driving force of the phase transition.

关键词： Phase transition Dielectric DSC Crystal structure

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Carbon isotopic composition and genetic types of natural gas in the Sichuan Basin, China

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Acta Geochimica 2017年第1期36卷 102-111页

作者： Jin-ning peng dong-yan wang Guang-xiang Liu Min Zhang Feng-li Li School of Earth Environment and Water Resources YangtzeUniversity Wuhan 430100 China Wuxi Research Institute of Petroleum Geology SINOPECWuxi 214126 Jiangsu China

The origin and genetic types of natural gas in the Sichuan Basin are still *** classify the origin and genetic types in different areas,the paper analyzes the carbon isotopic composition of gases and geologic features in the Sichuan *** results showed that the gas sourced from terrestrial layers is typically characterized by terrestrial origin and was mainly accumulated nearby to form *** carbon isotopic composition of gas showed a normal combination sequence distribution,suggesting that natural gas in continental strata is not affected by secondary alteration or that this deformation is very *** gas source is singular,and only gas from the southern and northern Sichuan Basin shows the characteristic of mixed ***,marine gas presents the characteristics of an oil-formed *** carbon isotopic composition of natural gas in the western and central part of the basin mostly distributes in a normal combination sequence,and few of them showed an inversion,indicating that the gas perhaps had not experienced secondary *** carbon isotopic composition of marine-origin gas in the southern,northern and eastern Sichuan Basin displays a completely different distribution pattern,which is probably caused by different mixing ratio of gas with multi-source and multi-period.

关键词： The Sichuan Basin Alkane Carbon isotope Genetic type

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Deformation behavior of Ta wire-reinforced Zr-based bulk metallic glass composites

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Journal of Iron and Steel Research International 2018年第6期25卷 601-607页

作者： Sen Chen Hua-meng Fu Zheng-kun Li Long Zhang Hong-wei Zhang Zheng-wang Zhu Hong Li Ai-min wang yan-dong wang Hai-feng zhang School of Materials Science and Engineering NortheasternUniversity Shenyang 110819 Liaoning China Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of SciencesShenyang 110016 Liaoning China dongguan Eontec Co. Ltd. Dongguan 523662 GuangdongChina Liaoning Jinyan Liquid Metal Technology Co. Ltd.Shenyang 110100 Liaoning China

A Ta wire-reinforced Zr-based bulk metallic glass composite with a new type of structure was prepared successfully by the method of liquid metal infiltration. Ta wires distribute uniformly in the metallic glass matrix in the form of spirals. The composite exhibits two yield stages under compressive stress, and the samples are compressed into thin pancakes. The micro-cracks originate at the interface between the Ta wire and the metallic glass matrix and propagate perpendicularly to the interface, which then induce multiple shear bands in the metallic glass matrix due to the stress concentration. Shear cracks form in the metallic glass matrix during the continued loading process as a result of the interaction of shear bands. Deformation bands of Ta wires occur under the impact of shear bands. The local stress fields in the composite are changed obviously due to the introduction of the spiral-formed reinforcements. The investigation of the deformation behavior and mechanism suggests a new method for the application of bulk metallic glass composites as the structural materials.

关键词： Bulk metallic glass composite Ta wire Spiral Shear band Deformation behavior

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Danhong Huayu Koufuye combined with metformin attenuated diabetic retinopathy in Zucker diabetic fatty rats

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International Journal of Ophthalmology(English edition) 2015年第6期8卷 1094-1100页

作者： Wen-Pei Chen yan-dong wang yan Ma Zi-yang Zhang Lu-Yun Hu Jun-Li Lin Bao-Qin Lin School of Chinese Materia Medica Guangzhou University of Chinese Medicine Zhongshan Ophthalmic Center Sun Yat-Sen University School of Chinese Materia Medica China Pharmaceutical University

AIM: To evaluate effects of Danhong Huayu Koufuye (DHK, a Chinese medicinal formulae) alone or combined with metformin on diabetic retinopathy (DR) in Zucker diabetic fatty (ZDF) rats, an animal model of obese type -2 diabetes, and then to investigate the mechanisms. METHODS: ZDF (fa/fa) rats were administered with vehicle (distilled water), metformin, DHK, and DHK plus metformin. Electrophysiological and histological analysis were applied to evaluated effects of DHK alone or combined with metformin on DR. The levels of fasting blood glucose (FBG) and glycosylated hemoglobin (HbA1c) in blood were measured to evaluate the antihyperglycemic activity of DHK. Furthermore, levels of nitric oxide (NO), malondialdehyde (MDA) and activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) in serum were measured to study effects of DHK on oxidative stress in ZDF rats. In addition, body weight, lipidic indexes and insulin level were also assessed. RESULTS: DHK combined with metformin significantly reversed the prolongation of latency times of flash electroretinogram (FERG) and oscillatory potentials (OPs) in diabetic rats. Furthermore, DHK alone or combined with metformin showed a remarkable suppression of retinal neovascularization and amelioration of retinal internal limiting membrane morphology. Moreover, DHK alone or plus metformin reduced FBG (P<0.05), HbA1c 1094 (P<0.01) and MDA (P<0.01) levels in diabetic rats. In addition, reductions in levels of triglycerides (TG) (P<0.01) and low density lipoprotein cholesterol (LDL-c) (P<0.01 and P<0.05, respectively) were also observed in diabetic rats treated with DHK alone or plus metformin. CONCLUSION: DHK in combination with metformin had a preventive and therapeutic effect on DR in type-2 diabetic rats, and the possible mechanisms may be alleviating hyperglycemia, reducing oxidative stress and improving lipid metabolism.

关键词： diabetic retinopathy Danhong HuayuKoufuye metformin Zucker diabetic fatty rat antihyperglycemic activity oxidative stress

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Protective effects of naringenin eye drops on N-methylN-nitrosourea-induced photoreceptor cell death in rats

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International Journal of Ophthalmology(English edition) 2014年第3期7卷 391-396页

作者： Jun-Li Lin yan-dong wang yan Ma Chun-Mei Zhong Mei-Rong Zhu Wen-Pei Chen Bao-Qin Lin School of Chinese Materia Medica Guangzhou University of Chinese Medicine Zhongshan Ophthalmic Center Sun Yat-Sen University Zhuhai United Laboratories Co. Ltd

AIM:To investigate the effects of naringenin eye drops on N-methyl-N-nitrosourea (MNU)-induced photoreceptor cell death in ***:Photoreceptor cell death was induced by single intraperitoneal injection of MNU(60 mg/kg)in *** eyes of all animals were instilled with one drop of vehicle,0.5% or 1.0% naringenin eye drops three times per day from 7d before to 17d after MNU *** of naringenin on MNU-induced photoreceptor cell death were evaluated by electrophysiological and histological ***:Flash electroretinography (FERG)and oscillatory potentials (OPs) recordings showed that the vehicle control group had remarkable reduction of amplitudes and prolongation of latency *** and OPs responses were significantly reversed in MNUinduced rats treated with 0.5%or 1.0% naringenin eye drops compared with the vehicle *** retinal morphological results showed that naringenin dosedependently preserved the outer nuclear layer,outer retina and total ***:These results indicate that topical treatment with naringenin eye drops prevented retinal neurons from MNU-induced structural and functional damages.

关键词： naringenin N-methyl-N-nitrosourea photoreceptor cell death retinitis pigmentosa

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