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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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Recent progress in diagnostic imaging and therapeutics of osteosarcoma based on multifunctional nanoparticles

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Science China Chemistry 2024年第9期67卷 2864-2889页

作者： Xueke yan Danmin Lin Dingyuan yan dong wang Huifang Su Department of Orthopaedic Surgery The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052China Center for AIE Research College of Materials Science and EngineeringShenzhen UniversityShenzhen 518060China

Osteosarcoma is one of the most common primary bone malignancies,mainly occurring in children and *** diagnosis imaging methods for osteosarcoma contain X-ray,computed tomography and magnetic resonance imaging,and traditional therapy protocols are surgical resection and ***,these strategies are complicated and *** imaging methods,despite their maturity,have drawbacks that prevent them from showing more *** is more,the prognosis for patients with osteosarcoma remains unsatisfactory due to side effects of chemotherapy,as well as incomplete surgical removal of the *** compensate for the shortcomings of traditional imaging and treatment strategies for osteosarcoma,various types of nanoparticles have been designed and synthesized to selectively target osteosarcoma cells without toxic side effects on healthy *** the same time,these nanoparticle-based technologies can integrate the imaging and treatment of *** review summarizes the application of nanotechnology in the imaging and treatment of osteosarcoma in recent years,and finally discusses the challenges and development prospects,aiming to provide ideas for future research.

关键词： osteosarcoma nanotechnology imaging diagnosis therapy

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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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Real-time model correction using Kalman filter for Raman-controlled cell culture processes

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Chinese Journal of Chemical Engineering 2024年第6期70卷 251-260页

作者： Xiaoxiao dong Zhuohong He Xu yan dong Gao Jingyu Jiao yan Sun Haibin wang Haibin Qu Pharmaceutical Informatics Institute College of Pharmaceutical SciencesZhejiang UniversityHangzhou 310058China Hisun Biopharmaceutical Co.Ltd. Hangzhou 311404China

Raman spectroscopy has found extensive use in monitoring and controlling cell culture *** this context,the prediction accuracy of Raman-based models is of paramount ***,models established with data from manually fed-batch cultures often exhibit poor performance in Raman-controlled ***,there is a need for effective methods to rectify these *** objective of this paper is to investigate the efficacy of Kalman filter(KF)algorithm in correcting Raman-based models during cell ***,partial least squares(PLS)models for different components were constructed using data from manually fed-batch cultures,and the predictive performance of these models was ***,various correction methods including the PLS-KF-KF method proposed in this study were employed to refine the PLS ***,a case study involving the auto-control of glucose concentration demonstrated the application of optimal model correction *** results indicated that the original PLS models exhibited differential performance between manually fed-batch cultures and Raman-controlled *** glucose,the root mean square error of prediction(RMSEP)of manually fed-batch culture and Raman-controlled culture was 0.23 and 0.40 g·L^(-1).With the implementation of model correction methods,there was a significant improvement in model performance within Raman-controlled *** RMSEP for glucose from updating-PLS,KF-PLS,and PLS-KF-KF was 0.38,0.36 and 0.17 g·L^(-1),***,the proposed PLS-KF-KF model correction method was found to be more effective and stable,playing a vital role in the automated nutrient feeding of cell cultures.

关键词： Raman spectroscopy Model correction Algorithm Model-predictive control Bioprocess

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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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A benchmark-based method for evaluating hyperparameter optimization techniques of neural networks for surface water quality prediction

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Frontiers of Environmental Science & Engineering 2024年第5期18卷 13-27页

作者： Xuan wang yan dong Jing yang Zhipeng Liu Jinsuo Lu School of Environmental and Municipal Engineering Xi’an University of Architecture and TechnologyXi’an710055China Shaanxi Key Laboratory of Environmental Engineering Xi’an University of Architecture and TechnologyXi’an710055China State Key Laboratory of Green Building in West China Xi’an University of Architecture and TechnologyXi’an710055China

Neural networks(NNs)have been used extensively in surface water prediction tasks due to computing algorithm improvements and data *** essential step in developing an NN is the hyperparameter *** practice,it is common to manually determine hyperparameters in the studies of NNs in water resources *** may result in considerable randomness and require significant computation time;therefore,hyperparameter optimization(HPO)is *** study adopted five representatives of the HPO techniques in the surface water quality prediction tasks,including the grid sampling(GS),random search(RS),genetic algorithm(GA),Bayesian optimization(BO)based on the Gaussian process(GP),and the tree Parzen estimator(TPE).For the evaluation of these techniques,this study proposed a method:first,the optimal hyperparameter value sets achieved by GS were regarded as the benchmark;then,the other HPO techniques were evaluated and compared with the benchmark in convergence,optimization orientation,and consistency of the optimized *** results indicated that the TPE-based BO algorithm was recommended because it yielded stable convergence,reasonable optimization orientation,and the highest consistency rates with the benchmark *** optimization consistency rates via TPE for the hyperparameters hidden layers,hidden dimension,learning rate,and batch size were 86.7%,73.3%,73.3%,and 80.0%,*** the evaluation of HPO techniques directly based on the prediction performance of the optimized NN in a single HPO test,the proposed benchmark-based HPO evaluation approach is feasible and robust.

关键词： Neural networks Hyperparameter optimization Surface water quality prediction Bayes optimization Genetic algorithm

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