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Parametrized Area Integrals on Hardy Spaces and Weak Hardy Spaces

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Acta Mathematica Sinica,English Series 2007年第9期23卷 1537-1552页

作者： Yong ding Shan zhen LU Qing Ying XUE School of Mathematical Science Beijing Normal University Beijing 100875 P. R. China

In this paper, the authors prove that if Ω satisfies a class of the integral Dini condition, then the parametrized area integral μΩ,S^ρ is a bounded operator from the Hardy space H1 （R^n） to L1 （R^n） and from the weak Hardy space H^1,∞ （R^n） to L^1,∞ （R^n）, respectively. As corollaries of the above results, it is shown that μΩ,S^ρ is also an operator of weak type These conclusions are substantial improvement and （1, 1） and of type （p,p） for 1 〈 p 〈 2, respectively extension of some known results.

关键词： area integral Hardy space weak Hardy space integral Dini condition

Criterion of Anisotropic Modes and Rejection Band in a Waveguide Filled with Cold Magnetoactive Plasma

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Chinese Physics Letters 1997年第5期14卷 364-366页

作者： ding zhen-feng REN Zhao-xing Institute of Plasma Physics Chinese Academy of SciencesHefei 230031

The dispersion equation characterizing quasi-static TE mode and the criterion for the existence of the anisotropic mode are *** characteristics of the rejection band and its bandwidth are investigated in comparison wi... 详细信息

关键词： Criterion conclusion criterion

Effect of fertilizer and water content on N_2O emission from three plantation soils in south China

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Journal of Environmental Sciences 2005年第6期17卷 970-976页

作者： LI Zhi-an ZOU Bi XIA Han-ping ding Yong-zhen TAN Wan-neng MA zhen-rong South China Botanical Garden Chinese Academy of Sciences Guangzhou 510650 China

The effects of fertilizers and water content on N2O emission were studied using the three most typical plantation soils. Soil incubations were performed and fertilization and water content treatments were designed. At 25% of saturated water content（SWC）, N2O emissions from the soil treated with urea, KNO3, （NH4）2 SO, and KH2 PO, were compared at application rates of 0, 100, 200, 300 and 500 kg/hm2. At 80% of SWC, similar experiments were carried out but at only one application rate（500 kg/hm^2）. N2O emissions at various water contents（20%, 35%, 50%, 65%, 80% and 100% of SWC） were studied. At low water content（25% of SWC）, neither nitrogen nor phosphorus（or potassium） fertilizers led to a high level of N2O emission, which generally ranged from 2.03 to 29.02 μg/（m^2·h）. However, at high water content（80% SWC）, the fertilizers resulted in much greater N2O emission irregardless of soil tested. The highest N2O emission rates after 24 h of water addition were 1233 lag/（ m^2 ·h） for S. superba soil, 1507 lag/（m^2 · h） for P. elliottii soil and 1869 lag/ （m^2 h） for A. mangium soil respectively. N2O emission from soils treated with urea, （NH4）2SO, and KH2PO, immediately dropped to a low level but steadily increased to a very high level for the soil treated with KNO3. High NO3^- content was a basis of high level of N2O emission. N2O emission rates from soils peaked shortly after flooding, rapidly dropping to a very low level in soil from non-legume plantations, but lasting for a relatively long period in soil from legume plantations. When soil water content increased equaling to or higher than 65%, the accumulated N2O emission over a period of 13 d ranged from 20.21-29.78 mg/m^2 for S. superba, 30.57-70.12 mg/m^2 for P. elliottii and 300.89-430.51 mg/m^2 for A. mangium. The critical water content was 50% of SWC, above which a high level of N2O emission could be expected, and below which very little N2O emissions were detected. The results suggest that, at low water content（

关键词： N2O plantation south China Acacia mangium Pinus elliottii Schima superba

Promoter methylation and mRNA expression of DKK-3 and WIF-1 in hepatocellular carcinoma

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World Journal of Gastroenterology 2009年第21期15卷 2595-2601页

作者： zhen ding Ye-Ben Qian Li-Xin Zhu Qi-Ru Xiong Department of Surgery First Affiliated Hospital of Anhui Medical University 218 Jixi avenue Hefei 230022 Anhui Province. China

AIM:To investigate the promoter methylation status and mRNA expression of DKK-3 and WIF-1 gene in hepatocellular carcinoma(HCC).METHODS:DKK-3 and WIF-1 acted as Wnt-antagonists and tumor suppressors,but hypermethylation of the gene promoter and low mRNA expression activated Wnt signaling aberrantly and induced the development of *** status of the DKK-3 and WIF-1 gene promoter was investigated using methylation specific polymerase chain reaction(PCR) in tumor and adjacent non-cancerous tissues from 33 HCC patients and 20 normal liver tissues served as *** expression of DKK-3 and WIF-1 mRNA was also determined by real-time quantitative reverse transcriptase *** relationship between methylation,mRNA expression,and clinical data,as well as methylation and mRNA expression of the two genes were ***:The methylation of DKK-3 and WIF-1 genes in HCC increased significantly compared with adjacent non-cancerous tissues and normal control tissues(χ2 =7.79,P < 0.05;χ2 = 4.89,P < 0.05),and no significant difference in methylation between adjacent non-cancerous tissues and normal control tissues was *** HCC tissues,significant differences in the DKK-3 promoter methylation were observed in age and cirrhosis,and significant differences of the WIF-1 promoter methylation were observed in HBsAg and *** average expression of DKK-3 mRNA in HCC and adjacent non-cancerous tissues was increased significantly compared with normal control *** average expression of WIF-1 mRNA showed no significant difference among the three *** mRNA expression of DKK-3 gene in HCC was decreased as the pathological grade ***:The aberrant promoter methylation and decreased expression of DKK-3 and WIF-1 may be an important mechanism in HCC,and may be a far-reaching significance in early diagnosis and therapy of HCC.

关键词： Hepatocellular carcinoma DKK-3 WIF-1 Promoter methylation

The assessment of personal exposure in restaurants considering heat sources and ventilation strategies

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Energy and Built Environment 2024年第5期5卷 657-664页

作者： Yilin Xie zhen ding Jianchao Ma Xiaohong zheng Fan Liu Yuqing ding Zhiyong Shu Hua Qian School of Energy and Environment Southeast UniversityNanjingJiangsu 210096China Department of Environment and Health Jiangsu Provincial Center for Disease Control and PreventionNanjing 210009China School of Environment and Architecture University of Shanghai for Science and TechnologyShanghai 200093China

Outbreaks of airborne infections during meal consumption in diverse restaurant settings have been extensively *** is widely recognized that effective ventilation strategies are essential to minimize the infection risk in indoor environments,and these strategies should be tailored to the heat *** purpose of this study is to compare the spatial distribution of risk in restaurant rooms that use mixing or displacement ventilation,specif-ically focusing on the heat sources used for different food types,namely hotpot,normal Chinese food,and iced *** Fluid Dynamics(CFD)was employed to assess exposure *** results indicate that the use of low-temperature heat sources can elevate the risk of infection by increasing the local vertical temperature *** comparison to no heat source,the risk increased by 190.9%and 99.6%for displacement and mixing ventilation strategies,*** mixing ventilation,both low-temperature and no heat sources showed lower infection risks when compared to displacement ***,displacement ventilation is found to be highly effective in reducing the risk of infection when using a high-temperature heat source,with only 12.3%of the infection risk observed in mixing ***,the use of displacement ventilation resulted in a significant reduction in the odors emitted by hotpot,which were instead absorbed by clothes in the mixing ven-tilation *** findings provide crucial insights into the development of appropriate ventilation strategies for reducing personal exposure to airborne infections in diverse restaurant ***,we recommend using displacement ventilation in restaurants that utilize high-temperature heat sources,as it can substantially reduce the risk of infection.

关键词： Heat source Building ventilation Airborne transmission Respiratory tract infections

Identification and Determination of Microcystins in Source Water and Waterbloom Sample From Meiliang Bay,Taihu Lake,China

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Biomedical and Environmental Sciences 2006年第3期19卷 225-231页

作者： XIAO-GANG FENG zhen ding TAO WEI CHUN-WEI YUAN DE-GANG FU The Key Laboratory of Molecular ＆ Biomolecular Electronics Department of Biomedical Engineering Southeast University Nanjing 210096 Jiangsu China Nanjing 210009 Jiangsu China

Objective To identify and determine the congener and level of microcystins in the source water of Taihu Lake. Methods Improved method of SPE combined with HPLC was employed to detect the concentration and varieties of microcystins in source water and bloom samples collected from Meiliang Bay, Taihu Lake. Results The contents of two predominant microcystin components, MC-RR, and MC-LR, were relatively high in samples during warm months and correlated with the phase of algae growth. The maximum concentrations of MC-RR and MC-LR in water sample reached 3.09±0.53μg/L and 2.39±0.41μg/L during the period of water bloom in September 2004, respectively. Even without waterbloom, the concentration of MC-LR in source water sample was still higher than the guideline value. Conclusion The status of microcystin pollution in this region is serious and measures to monitor and control the growth of cyanobacteria are urgently needed.

关键词： Microcystin Determination Source water HPLC Taihu Lake

Preparation of spin squeezed state in SiV centers coupled by diamond waveguide

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Chinese Physics B 2021年第10期30卷 165-170页

作者： Yong-Hong Ma Yuan Xu Quan-zhen ding Yu-Sui Chen School of Science Inner Mongolia University of Science and TechnologyBaotou 014010China Department of Physics and Center for Quantum Science and EngineeringStevens Institute of TechnologyHobokenNJ 07030USA Department of Physics New York Institute of TechnologyOld WestburyNY 11568USA

Spin squeezing is a fascinating manifestation of many-particle entanglement and one of the most promising quantum *** this paper,we propose a novel realization of a solid-state quantum spin squeezing by applying SiV centers embedded in a diamond waveguide with the help of a microwave *** phenomena about the generation of spin squeezing are analyzed numerically in Markovian *** analysis shows that spin squeezing can be generated with the microwave field’s help under some realistic conditions,despite the presence of dephasing and mechanical *** solid-state spin squeezing based on SiV centers in diamonds might be applied to magnetometers,interferometry,and other precise measurements.

关键词： spin squeezed state SiV center diamond waveguide

Adaptive　Multisensor　Tracking　Fusion　Algorithm　for　Air－borne　Distributed　Passive　Sensor　Network

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Journal of Systems Engineering and Electronics 1996年第3期7卷 15-23页

作者： zhen ding Hongcai Zhang & Guanzhong Dai (Department of Automatic Control, Northwestern Polytechnical UniversityShaanxi, Xi’an 710072, P.R.China) Department of Automatic Control Northwestern Polytechnical University Shaanxi Xi'an 710072 P.R. China

Single passive sensor tracking algorithms have four disadvantages: bad stability, longdynamic time, big bias and sensitive to initial conditions. So the corresponding fusion algorithm results in bad performance. A new error analysis method for two passive sensor tracking system is presented and the error equations are deduced in detail. Based on the equations, we carry out theoretical computation and Monte Carlo computer simulation. The results show the correctness of our error computation equations. With the error equations, we present multiple 'two station'fusion algorithm using adaptive pseudo measurement equations. This greatly enhances the tracking performance and makes the algorithm convergent very fast and not sensitive to initial *** results prove the correctness of our new algorithm.

关键词： Passive tracking system Error analysis Fusion algorithm Distributed passive sensornetwork Distributed estimation.

Effect of Additives on Melting Point of LATS Refining Ladle Slag

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Journal of Iron and Steel Research International 2007年第2期14卷 25-29页

作者： WANG Hong-ming LI Gui-rong ding zhen-tao DAI Qi-xun LI Bo School of Material Science and Engineering Jiangsu University Zhenjiang 212013 Jiangsu China Stainless Steel Branch Baosteel Group Shanghai 200431 China

To avoid slag sticking on the ladle immersion cover during the LATS refining and alloying process, the effect of Al2O3 on the melting point of the ladle slag was studied and the additives including CaF2, B2O3, Li2O, and CaO were used to decrease the melting point of the ladle slag. The melting point was measured using the hemisphere method. The results show that the addition of Al2O3 to the ladle slag increases the melting point. The fluxing action is not remarkable if only CaF2 or CaO is used as the additive. The fluxing action of the composite additive obtained by the mixing of CaO and CaF2 in the mass proportion of ωCaO：ωCaF2=2 ： 1 is preferred. The fluxing action of B2O3 is also notable. When the B2O3 content in mass percent is in the range from 2% to 10%, the corresponding melting point is 1 380 ℃ to 1 290℃. The fluxing action of Li2O is the most remarkable. When the Li2O content is up to 5%, the melting point of the slag is lower than 1 300 ℃.

关键词： LATS refining ladle slag melting point additive immersion cover