|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | Penetration characteristics of VLF wave from atmosphere into lower ionosphere显示文摘The factors affecting the reflection and transmission coefficient of the ionosphere have been analyzed.These factors include wave frequency,incident angle,geomagnetic inclination,electron density and collision frequency in the ionosphere.The ionosphere refractive index is also analyzed.The ionosphere above 70 km is considered to be homogeneous and anisotropic,and the reflection and transmission coefficient matrix is calculated using matrix method.Simultaneously the Booker quartic equation is solved to get the refractive index in the ionosphere.The results show that when the wave frequency is higher,it is easier to penetrate into the ionosphere from its bottom boundary and the propagation attenuation in the ionosphere is smaller.TE(traverse electric) wave and TM(traverse magnetic) wave can both penetrate into the ionosphere with a small incident angle,while TE wave can hardly transmit into the ionosphere when the incident angle is large.The transmission coefficient decreases as the geomagnetic inclination increases.TE and TM wave cannot penetrate into the ionosphere at magnetic equator.When the electron collision frequency is higher,it is easier for VLF wave to penetrate into the ionosphere and the attenuation of ordinary wave is weaker,which may be caused by the energy transportation between the waves and the particles.The ordinary(O) wave experiences severer attenuation than extraordinary(X) wave,and X wave is a penetration mode whereas O wave is a non-penetration mode in the ionosphere.All the results indicate that VLF wave with higher frequency is easier to penetrate into the ionosphere and to be recorded by the satellites at high latitude.It is hard for ULF and the lower frequency VLF wave to transmit into the ionosphere directly for the severe reflection and attenuation.It may transmit into the ionosphere with a small incident angle due to the nonlinear effect,for example,the interaction between the waves and the particles or cross modulation,and then propagate along the whistle duct with small attenuation.This work may be a preliminary theoretical exploration for the future calculation on the response of ground based VLF artificial transmitter in the ionosphere and further study on the seismic ionosphere coupling model. | Shufan Zhao Xuhui Shen Weiyan Pan Xuemin Zhang Li Liao | 2010 | Earthquake Science2010，23，3： | 8 |
| 2 | Inflammation,epigenetics,and metabolism converge to cell senescence and ageing:the regulation and intervention显示文摘Remarkable progress in ageing research has been achieved over the past decades.General perceptions and experimental evidence pinpoint that the decline of physical function often initiates by cell senescence and organ ageing.Epigenetic dynamics and immunometabolic reprogramming link to the alterations of cellular response to intrinsic and extrinsic stimuli,representing current hotspots as they not only(re-)shape the individual cell identity,but also involve in cell fate decision.This review focuses on the present findings and emerging concepts in epigenetic,inflammatory,and metabolic regulations and the consequences of the ageing process.Potential therapeutic interventions targeting cell senescence and regulatory mechanisms,using state-of-the-art techniques are also discussed. | Xudong Zhu Zhiyang Chen Weiyan Shen Gang Huang John M.Sedivy Hu Wang Zhenyu Ju | 2021 | Signal Transduction and Targeted Therapy2021，6，7： | 2 |
| 3 | Serum MicroRNA Expression Profile as a Biomarker in the Diagnosis and Prognosis of Pancreatic Cancer显示文摘 | Liu Rui Chen Xi Du Yiqi Yao Weiyan Shen Lin Wang Cheng Hu Zhibin Zhuang Rui Ning Guang Zhang Chunni Yuan Yaozong Li Zhaoshen Zen Ke Ba Yi Zhang Chen-Yu | 2012 | Clinical Chemistry2012，，3： | 2 |
| 4 | Life satisfaction approach to farmers' compensation for land acquisition:empirical study from the suburbs of Wuhan City显示文摘Farmers' compensation for land acquisition is not only critical to increasing their income and to playing a pivotal role in maintaining rural stability,but also to the promotion of sustainable land use.Based on analysis of Chinese land acquisition policy under the Land Management Law,which provides principles or guidelines for determining compensation according to agricultural land use in regard to farmers' previous quality of life,the Life Satisfaction Approach is introduced in this article to evaluate farmers' compensation for land acquisition.Employing data from a questionnaire survey on 346 farming households in Wuhan Suburbs,this article examined the influence of farmland on farmers' life satisfaction and evaluated the level of compensation for land acquisition.Results show that farmland has a significantly positive impact on life satisfaction,which fell by 0.033 on a five-point scale following a reduction farmland by of 1 mu.Respondents were willing to accept approximately RMB 3066.44 annual household income for the loss of 1 mu farmland;the level of compensation after discounting by 6.2%is RMB 750,000 per hectare.It was found in a further comparative study that the level of farmers' compensation for land acquisition is decidedly low,and it was also shown that their compensation standards,as well as the actual compensation,could be substantially improved by expanding economic compensation to non-economic compensation to embody farmland multifunction in terms of production and non-production against farmers' previous quality of life.This article proposes a compensation model that enriches the content of land acquisition compensation,extends the current literature on measuring compensation,and provides economic theory bases for increasing compensation standards and improving policies related to land acquisition.We consider that if this compensation model is applied,it could raise the cost of land acquisition and improve usage of land,reduce the speed of rural-urban land conversion,and improve farmers' well-being. | Weiyan Hu Xuelong Zhang Yan Song Long Shen Jin Liu Anlu Zhang | 2014 | Chinese Journal of Population,Resources and Environment2014，12，4： | 1 |
| 5 | A Cross-layer Design Approach to Multicast in Wireless Networks显示文摘 | Ge Weiyan Zhang Junshan Shen Sherman | | 0，，03： | 1 |
| 6 | Association Between Methionine Synthase Reductase A66G Polymorphism and the Risk of Congenital Heart Defects: Evidence From Eight Case–Control Studies显示文摘 | Di Yu Lei Yang Shutong Shen Changfeng Fan Weiyan Zhang Xuming Mo | 2014 | Pediatric Cardiology2014，，7： | 1 |
| 7 | Clue to a New Deafness Gene:A Large Chinese Nonsyndromic Hearing Loss Family Linked to DFNA4显示文摘Hereditary hearing loss is one of the most common neurosensory defects in humans.Approximately 70%of cases are nonsyndromic and could be inherited in autosomal dominant, autosomal recessive,mitochondrial,X-linked,and Y-linked manners(Wang et al.,2004;Alford,2011).The autosomal dominant type,comprising 15%-20%of nonsyndromic hearing loss,is monogenic and genetically heterogeneous.Since the first dominant deafness | Liang Zong Chunye Lu Yali Zhao Qian Li Dongyi Han Weiyan Yang Yan Shen Qingyin Zheng Qiuju Wang | 2012 | Journal of Genetics and Genomics2012，39，12： | 0 |
| 8 | Direct visualization of percolating metal-insulator transition in V_(2)O_(3) using scanning microwave impedance microscopy显示文摘Using the extensively studied V_(2)O_(3) as a prototype system, we investigate the role of percolation in metal-insulator transition(MIT). We apply scanning microwave impedance microscopy to directly determine the metallic phase fraction p and relate it to the macroscopic conductance G, which shows a sudden jump when p reaches the percolation threshold. Interestingly, the conductance G exhibits a hysteretic behavior against p, suggesting two different percolating processes upon cooling and warming. Based on our image analysis and model simulation, we ascribe such hysteretic behavior to different domain nucleation and growth processes between cooling and warming, which is likely caused by the decoupled structural and electronic transitions in V_(2)O_(3) during MIT. Our work provides a microscopic view of how the interplay of structural and electronic degrees of freedom affects MIT in strongly correlated systems. | Weiyan Lin Huanyu Zhang Yoav Kalcheim Xinchen Zhou Fubao Yang Yang Shi Yang Feng Yihua Wang Jiping Huang Ivan KSchuller Xiaodong Zhou Jian Shen | 2022 | Science China(Physics,Mechanics & Astronomy)2022，65，9： | 0 |
| 9 | Nicotinamide adenine dinucleotide replenishment rescues colon degeneration in aged mice显示文摘Susceptibility of gastrointestinal dysmotility increases with age-associated colonic degeneration.A paucity of remedies reversing colonic degeneration per se hinders the fundamental relief of symptoms.Here we discovered the correlation between colon degeneration and altered nicotinamide adenine dinucleotide(NAD)level in aged mice.Compared to 3-month-old young controls,2-year-old mice showed a spectrum of degenerative colonic phenotypes and exhibited a significant elongated transit time and slowed stool frequency in the context of Lomotil-induced slow-transit constipation.Despite upregulated colonic tryptophan hydroxylases expression,serotonin release and expression of colon-predominant type IV serotonin receptor,reduced viability of interstitial cells of Cajal while enhanced aquaporins(Aqp1,3 and 11)led to a less colonic motility and increased luminal dehydration in aged mice.Notably,this colonic degeneration was accompanied with reduced key NAD^(+)-generating enzyme expression and lowered NAD^(+)/NADH ratio in aged colon.Three-month continuous administration of beta nicotinamide mononucleotide,a NAD^(+)precursor,elevated colonic NAD^(+)level and improved defecation in aged mice.In contrast,pharmacological inhibition of nicotinamide phosphoribosyltransferase,the rate-limiting enzyme for NAD^(+)biosynthesis,induced a reduction in colonic NAD content and impaired gastrointestinal function in young mice.Taken together,these findings suggest the beneficial effect of NAD^(+)in maintaining colonic homoeostasis and reactivating NAD^(+)biosynthesis may represent a promising strategy to counteract age-related gastrointestinal degeneration. | Xudong Zhu Weiyan Shen Ying Wang Amit Jaiswal Zhenyu Ju Qinsong Sheng | 2017 | Signal Transduction and Targeted Therapy2017，2，1： | 0 |
| 10 | Rational design of Ni-MoO_(3–x) catalyst towards efficient hydrodeoxygenation of lignin-derived bio-oil into naphthenes显示文摘Design of a robust catalyst with high activity but the low cost for the hydrodeoxygenation(HDO) of biooils is of great importance to bring the biorefinery concept into reality.In this study,density functional theory(DFT) calculation was adopted to analyze the optimal location of Ni on MoO_(3-x) containing oxygen vacancy,and the corresponding result demonstrated that metallic Ni cluster located at the neighborhood of oxygen vacancies would significantly evoke HDO activity.Enlightened by DFT results,NiMoO_(4) was first hydrothermally synthesized and then employed to fabricate Ni-MoO_(3-x) catalyst via a low-temperature reduction,where Ni escaped from NiMoO_(4) and was reduced to its metallic state.Such an evolution of Ni species also induced the formation of oxygen vacancies around metallic Ni cluster.In the HDO of p-cresol,Ni-MoO_(3-x) exhibited high activity with a complete conversion and a methylcyclohexane selectivity of 99.4% at 150℃.Moreover,the catalyst showed good versatility in catalyzing HDO of diverse lignin-derived oxygenates and lignin oil.2D HSQC NMR,gas chromatograph and elemental analysis of the lignin oil demonstrated the high deoxygenation efficiency and saturation of the benzene ring over Ni-MoO_(3-x).In the upgrading of crude lignin oil,the deoxygenation degree was up to 99%,and the overall carbon yield of the naphthenes was as high as 69.4%.Importantly,the structures and carbon numbers of the naphthene products are similar to jet fuel-range cycloalka nes,which are expected to have a high density that can be blended into jet fuel to raise the range(or payload) of airplanes.This work demonstrates the feasibility for improving the targeted catalytic reactivity by rational tailoring the catalyst structure under the guidance of theoretical analysis,and provides an energy-efficient route for the upgrading of lignin crude oil into valuable naphthenes. | Chao Wang Luxian Guo Kui Wu Xinxin Li Yanping Huang Zhigang Shen Hongyun Yang Yunquan Yang Weiyan Wang Changzhi Li | 2023 | Journal of Energy Chemistry2023，，9： | 0 |
| 11 | On‑Ramp Merging for Highway Autonomous Driving:An Application of a New Safety Indicator in Deep Reinforcement Learning显示文摘This paper proposes an improved decision-making method based on deep reinforcement learning to address on-ramp merging challenges in highway autonomous driving.A novel safety indicator,time difference to merging(TDTM),is introduced,which is used in conjunction with the classic time to collision(TTC)indicator to evaluate driving safety and assist the merging vehicle in finding a suitable gap in traffic,thereby enhancing driving safety.The training of an autonomous driving agent is performed using the Deep Deterministic Policy Gradient(DDPG)algorithm.An action-masking mechanism is deployed to prevent unsafe actions during the policy exploration phase.The proposed DDPG+TDTM+TTC solution is tested in on-ramp merging scenarios with different driving speeds in SUMO and achieves a success rate of 99.96%without significantly impacting traffic efficiency on the main road.The results demonstrate that DDPG+TDTM+TTC achieved a higher on-ramp merging success rate of 99.96%compared to DDPG+TTC and DDPG. | Guofa Li Weiyan Zhou Siyan Lin Shen Li Xingda Qu | 2023 | Automotive Innovation2023，6，3： | 0 |
您所在的机构暂未开通此部分的功能，请联系管理员