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临时阴极保护在长输天然气管道中的应用 预览
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作者 姜泉涛 《全面腐蚀控制》 2020年第2期28-30,共3页
山东某管道设计采用外加电流阴极保护系统,由于场站变更等原因,阴极保护站无法确定位置及施工,线路中采用牺牲阳极临时保护措施对管道进行短期的保护。
关键词 长输管道 通电电位 断电电位 临时保护
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A Prudent Approach Is Key to Leveraging the China Opportunity
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《中国与非洲:英文版》 2020年第3期48-49,共2页
China has a population of1.4 billion,representing hundreds of millions of consumers.As the world’s second-largest economy continues its unique growth story,the Chinese consumer’s buying power is increasing,and so is... China has a population of1.4 billion,representing hundreds of millions of consumers.As the world’s second-largest economy continues its unique growth story,the Chinese consumer’s buying power is increasing,and so is the world’s desire to tap into that revenue potential. 展开更多
关键词 REVENUE potential. CONSUMER
Distribution and Functional Characteristics of Voltage-Gated Sodium Channels in Immature Cochlear Hair Cells
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作者 You Zhou Chenchen Xia +3 位作者 Manli Yi Xueling Wang Hao Wu Yonghua Ji 《神经科学通报:英文版》 SCIE CAS CSCD 2020年第1期49-65,共17页
Voltage-gated sodium channels(VGSCs)are transiently expressed in cochlear hair cells before hearing onset and play an indispensable role in shaping spontaneous activity.In this study,we showed that Na^+currents shaped... Voltage-gated sodium channels(VGSCs)are transiently expressed in cochlear hair cells before hearing onset and play an indispensable role in shaping spontaneous activity.In this study,we showed that Na^+currents shaped the spontaneous action potentials in developing mouse inner hair cells(IHCs)by decreasing the time required for the membrane potential to reach the action-potential threshold.In immature IHCs,we identified 9 known VGSC subtypes(Navl.la-l.9ot),among which Navl.7a was the most highly expressed subtype and the main contributor to Na+currents in developing hair cells.Electrophysiological recordings of two cochlea-specific Navi.7 variants(CbmNavl.7a and CbmNavl.7b)revealed a novel loss-of-function mutation(C934R)at the extracellular linker between segments 5 and 6 of domain II.In addition,post-transcriptional modification events,such as alternative splicing and RNA editing,amended the gating properties and kinetic features of CbmNavl.7a(C934).These results provide molecular and functional characteristics of VGSCs in mammalian IHCs and their contributions to spontaneous physiological activity during cochlear maturation. 展开更多
关键词 Cochlear hair cell Spontaneous action potential Voltage-gated sodium channel Post-transcriptional modification Gating property Introduction
玉米自交系XZ966-14的利用潜势研究
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作者 霍仕平 冯云超 +3 位作者 晏庆九 羊炼 向振凡 张芳魁 《玉米科学》 CAS CSCD 北大核心 2020年第1期17-24,共8页
以美国玉米种质为基础材料创制出自交系XZ966-14,经改良后育成WZ049、WZ0714、WZ126、WZ1422和WZ1423共5个衍生系,采用NCⅡ交配设计测定XZ966-14及其衍生系的配合力,应用全基因组SNP芯片技术检测XZ966-14及其衍生系的遗传潜势。结果表明... 以美国玉米种质为基础材料创制出自交系XZ966-14,经改良后育成WZ049、WZ0714、WZ126、WZ1422和WZ1423共5个衍生系,采用NCⅡ交配设计测定XZ966-14及其衍生系的配合力,应用全基因组SNP芯片技术检测XZ966-14及其衍生系的遗传潜势。结果表明,XZ966-14产量配合力高,与Reid、旅大红骨种质衍生系杂交有较强杂交优势。该自交系的衍生系产量配合力好,与旅大红骨种质衍生系、PN(PA和PB)种质衍生系杂交有较强杂交优势。全基因组SNP芯片检测结果显示,WZ049、WZ0714、WZ126在第1~10染色体上均遗传了XZ966-14基因组片段,其长度占整条染色体总长的比例最大为100%,最小为3.04%;XZ966-14第4、6、7染色体上具有较强的遗传传递能力,能将其大部分甚至全部遗传信息稳定传递给所有衍生系;第2、3染色体也有较强的遗传传递能力,能将其大量遗传信息传递给大部分衍生系。在产量配合力育种方面,XZ966-14还有较大的育种潜力。 展开更多
关键词 玉米 自交系 衍生系 配合力 遗传潜势 利用潜势
Formation control and collision avoidance for multi-UAV systems based on Voronoi partition
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作者 HU JinWen WANG Man +2 位作者 ZHAO ChunHui PAN Quan DU Chang 《中国科学:技术科学英文版》 SCIE EI CAS CSCD 2020年第1期65-72,共8页
This paper deals with the formation control problem of multiple unmanned aerial vehicles(UAVs) with collision avoidance. A distributed formation control and collision avoidance method is proposed based on Voronoi part... This paper deals with the formation control problem of multiple unmanned aerial vehicles(UAVs) with collision avoidance. A distributed formation control and collision avoidance method is proposed based on Voronoi partition and conventional artificial potential field. The collision avoidance is achieved by partitioning the whole space into non-overlapping regions based on Voronoi partition theory, which is taken as the task region to confine the movement of each UAV. The general motion control law is designed based on the conventional artificial potential field. As this often leads to local optimum when two UAVs are going to collide with each other and they may stay still where the repulsive force is adversely equivalent to the attractive force. To address this problem,the destination switch scheme is further proposed to let UAVs switch destinations when they reach the local equilibrium. Finally,the effectiveness of proposed formation control algorithm is validated by simulations and experiments. 展开更多
关键词 unmanned aerial vehicles formation control Voronoi partition artificial potential field
Neurodynamics analysis of cochlear hair cell activity 预览
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作者 Weifeng Rong Rubin Wang +1 位作者 Jianhai Zhang Wanzeng Konga 《力学快报:英文版》 CAS CSCD 2020年第1期8-15,共8页
There have been many studies on the effect of cochlea basal membrane movement on the resolution of different frequencies and intensities.However,these studies did not take into account the influence of power and energ... There have been many studies on the effect of cochlea basal membrane movement on the resolution of different frequencies and intensities.However,these studies did not take into account the influence of power and energy consumption of the hair cells in the process of the electromotility movement,as well as the neurodynamic mechanism that produced this effect.This makes previous studies unable to fully clarify the function of outer hair cells(OHCs)and the mechanism of sound amplification.To this end,we introduce the gate conductance characteristics of the hair cells in the mechanical process of increasing frequency selectivity.The research finds that the low attenuation of OHCs membrane potential and the high gain in OHC power and energy consumption caused that OHC amplification is driven by electromotility.The research results show that the amplification of the OHCs is driven by low attenuation of membrane potential and high gain of power and energy consumption.This conclusion profoundly reveals the physiological mechanism of the electromotility movement. 展开更多
关键词 Hair cells Sound frequencies Membrane potential POWER Outer hair cell amplification
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Take precautions against potential threats that carbon nanotubes may bring to you
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作者 Min Luo Ziying Xiang Zhanjun Gu 《中国科学:化学英文版》 SCIE EI CAS CSCD 2020年第2期141-142,共2页
Long-term pulmonary exposure to multi-walled carbon nanotubes (MWCNTs) may promote breast cancer metastasis and rapid colonization in the lungs and other organs according to recent research conducted by Prof.Chunying ... Long-term pulmonary exposure to multi-walled carbon nanotubes (MWCNTs) may promote breast cancer metastasis and rapid colonization in the lungs and other organs according to recent research conducted by Prof.Chunying Chen,Prof.Tao Zhu and their colleagues,published in Nature Nanotechnology [1]. 展开更多
关键词 carbon POTENTIAL ORGANS
硫铜钴矿浮选行为研究 预览
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作者 于志超 吴熙群 +3 位作者 王立刚 胡志强 田祎兰 李俊旺 《有色金属:选矿部分》 CAS 北大核心 2020年第1期18-23,共6页
对硫铜钴矿纯矿物在采用不同药剂条件下的浮选行为进行了研究。试验表明,丁基黄药对硫铜钴矿捕收作用较好,适当增加起泡剂松醇油用量可提高硫铜钴矿浮选回收率。矿浆pH值对硫铜钴矿可浮性存在影响,当pH值为8.19时回收率最低,pH值为10.8... 对硫铜钴矿纯矿物在采用不同药剂条件下的浮选行为进行了研究。试验表明,丁基黄药对硫铜钴矿捕收作用较好,适当增加起泡剂松醇油用量可提高硫铜钴矿浮选回收率。矿浆pH值对硫铜钴矿可浮性存在影响,当pH值为8.19时回收率最低,pH值为10.88时回收效果最佳。调整剂Na2S、NaHS在硫铜钴矿浮选中均表现出低用量活化、高用量抑制效果,总体而言NaHS活化效果要优于Na2S,电位测试表明相同质量浓度的NaHS比Na2S对矿浆电位的影响更大。 展开更多
关键词 硫铜钴矿 硫化钠 硫氢化钠 可浮性 电位
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Resilience Amid Challenges
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作者 Michael Zakkour 《北京周报:英文版》 2020年第8期38-39,共2页
The growth,scale and scope of the novel coronavirus outbreak in China has be-come one of the most talked about global subjects.The virus is first and foremost a domes-tic health issue for China,with an increasing inte... The growth,scale and scope of the novel coronavirus outbreak in China has be-come one of the most talked about global subjects.The virus is first and foremost a domes-tic health issue for China,with an increasing international potential.President Xi Jinping is leading a national effort to contain the outbreak while scientists and doctors in China and around the world are working to find a vaccine and/or cure. 展开更多
关键词 potential. DOMES DOCTOR
我国秸秆资源养分还田利用潜力及技术分析 预览
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作者 李一 王秋兵 《中国土壤与肥料》 CAS CSCD 北大核心 2020年第1期119-126,共8页
我国秸秆资源量丰富,且含有大量的养分,将这些养分还田利用,不但可以减少化肥的投入,还可以避免资源浪费,保护生态环境。通过资料收集和数据统计,对我国的秸秆资源状况、空间分布、养分利用潜力及养分还田技术进行了分析。结果显示:201... 我国秸秆资源量丰富,且含有大量的养分,将这些养分还田利用,不但可以减少化肥的投入,还可以避免资源浪费,保护生态环境。通过资料收集和数据统计,对我国的秸秆资源状况、空间分布、养分利用潜力及养分还田技术进行了分析。结果显示:2017年我国秸秆资源量约为8.55亿t,秸秆全量还田养分输入量分别为758.66万t(N)、238.84万t(P2O5)、1 316.36万t(K2O),分别可替代当年约34.15%的氮肥、29.95%的磷肥、212.40%的钾肥。根据当年秸秆综合利用情况和养分还田率,还田的养分可替代约19.38%的氮肥、23.28%的磷肥、166.81%的钾肥。相比秸秆全量还田,实际还田养分的可替代化肥率还有较大的提升潜力。此外,秸秆中还含有34 238.94万t的有机碳(未包括棉花秸秆),按30%的转化率计算,将有超过10 000万t的有机碳进入土壤。选取我国秸秆养分量最高的3个区域,对其秸秆养分还田技术进行分析,并提出在东北地区应以秸秆粉碎翻耕或旋耕还田为主,定期进行深翻作业;黄淮海地区应以小麦秸秆粉碎后覆盖以及玉米秸秆粉碎后旋耕或深耕还田为主,增加耕翻深度,及时将秸秆还田,定期进行深翻或深松作业;长江中下游地区应以秸秆粉碎旋耕混埋还田技术为主,严格控制机械切碎长度和旋耕深度。此外,在东北和黄淮海地区应将过腹还田与堆沤还田作为机械化直接还田的重要补充,在长江中下游地区应推广秸秆腐熟还田技术。 展开更多
关键词 秸秆还田 养分 潜力 还田技术
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Collagen crosslinking with photoactivated riboflavin in advanced infectious keratitis with corneal melting: Electrophysiological Study
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作者 Eman A.Awad Mona Abdelkader +2 位作者 Ameera G.Abdelhameed Walid M.Gaafar Tharwat H.Mokbel 《国际眼科杂志:英文版》 SCIE CAS 2020年第4期574-579,共6页
AIM: To assess the effect of photoactivated chromophore for keratitis crosslinking(PACK-CXL) in case of severe keratitis with melting on the electrophysiological function of the retina and the optic nerve.METHODS: The... AIM: To assess the effect of photoactivated chromophore for keratitis crosslinking(PACK-CXL) in case of severe keratitis with melting on the electrophysiological function of the retina and the optic nerve.METHODS: The study included 32 eyes of 32 patients with smear positive severe infectious keratitis with corneal melting. The patients were randomly divided into two groups. Group I(control group) included 16 eyes received systemic and topical antimicrobial drugs guarded by culture and sensitivity test. Group II underwent CXL and then continued their antimicrobial treatment. Full field electroretinogram(ERG) and flash visual evoked potential(VEP) were done for each patient in both groups basically and then 1 wk, 1 and 3 mo post-treatment to assess the changes in the electrophysiological function of the retina and optic nerve.RESULTS: Healing of 10 eyes in group I in comparison to 14 eyes in group II was recorded. The mean duration of healing was 36.56±5.21 d in group I vs 20.2±4.4 d in group II(P<0.005). In group II, ERG showed an insignificant reduction of all parameters of ERG and VEP after CXL. The amplitude of scotopic rod response, oscillatory potential amplitude, flicker amplitude and photopic cone response were insignificantly decreased(P=0.4, 0.8, 0.1, and 0.3 respectively). There were insignificant prolongation of latencies of scotopic rod, oscillatory potential, flicker and photopic cone response(P=0.2, 0.7, 0.5 and 0.1). There was slight delay in latency of VEP without a significant reduction in amplitude.CONCLUSION: CXL is an effective technique in treatment of severe infectious keratitis with melting as it halts the melting process with acceptable safety on the retinal and optic nerve function. 展开更多
关键词 photoactivated chromophore for keratitis crosslinking infectious keratitis corneal melting ELECTRORETINOGRAM flash visual evoked potential
Skyrmion stability at finite isospin chemical potential and temperature
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作者 苑文莉 徐珍妮 +1 位作者 张金利 宗红石 《中国物理C:英文版》 SCIE CAS CSCD 2020年第1期105-110,共6页
The skyrmion stability at finite isospin chemical potentialμ_I is studied using the Skyrme Lagrangian with a finite pion mass m_π.A critical valueμ_(Ic)=■,above which a stable soliton does not exist,is found.We al... The skyrmion stability at finite isospin chemical potentialμ_I is studied using the Skyrme Lagrangian with a finite pion mass m_π.A critical valueμ_(Ic)=■,above which a stable soliton does not exist,is found.We also explore some properties of the skyrmion as function of i.e.,the isoscalar rms radius and the isoscalar magnetic rms radius.Finally,considering the finite temperature effect on the skyrmion mass,we obtain a critical temperature T_c,using the profile function of the skyrmion,above which the skyrmion mass does not have a minimum,which can be interpreted as the occurrence of the deconfinement phase transition. 展开更多
关键词 skyrme model isospin chemical potential skyrmion stability
周末加油站(Ⅰ) 预览
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作者 《疯狂英语:读写版》 2020年第1期56-59,64共5页
Task 1 Mulan·March 27th,2020·Adventure When the Emperor of China issues a decree that one man per family must serve in the Imperial Army to defend the country from northern invaders,Hua Mulan,the eldest daug... Task 1 Mulan·March 27th,2020·Adventure When the Emperor of China issues a decree that one man per family must serve in the Imperial Army to defend the country from northern invaders,Hua Mulan,the eldest daughter of an honored warrior,steps in to take the place of her sick father.Masquerading as a man,Hua Jun,she is tested in every step of the way and must harness her inner-strength and embrace her true potential.It is an epic journey that will transform her into an honored warrior. 展开更多
关键词 potential. DAUGHTER STEPS
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Comparison of light absorption and oxidative potential of biodiesel/diesel and chemicals/diesel blends soot particles
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作者 Yu Kuang Yi Guo +4 位作者 Jiaqi Chai Jing Shang Jiali Zhu Svetlana Stevanovic Zoran Ristovski 《环境科学学报:英文版》 SCIE EI CAS CSCD 2020年第1期184-193,共10页
Soot particles,mainly coming from fuel combustion,affect climate forcing through absorbing light and also result in adverse human health outcomes.Though biodiesel or additives blending with diesel was considered envir... Soot particles,mainly coming from fuel combustion,affect climate forcing through absorbing light and also result in adverse human health outcomes.Though biodiesel or additives blending with diesel was considered environmentally friendly,the understanding on absorbing and oxidative capacity of soot emitted from them are still unclear.The watersoluble organic carbon(WSOC)content,surface chemical structure,light absorption and oxidative potential(OPDTT)of soot from biodiesel/diesel and chemicals/diesel blends were investigated utilizing total organic carbon analyzer,X-ray photoelectron spectrometer,ultraviolet–visible spectrophotometry and dithiothreitol(DTT)assay.The differences and correlations between soot properties were statistically analyzed.Chemicals/diesel blends soot owned significantly higher WSOC content,ratio of mass absorbing efficiency(MAE)in250 and 365 nm(E2/E3),OPDTT,and higher surface carbonyl content.Coconut biodiesel/diesel blends soot contained evidently higher aromatic carbon–oxygen single bond(ArC–O)content,and higher MAE365.The individual comparison of biodiesel/diesel blends showed20%coconut biodiesel blend owned the lowest WSOC,E2/E3 and OPDTT,while highest ArC–O and MAE365,representing strongest absorbing properties.Association analysis showed OPDTTwas significantly positively correlated with WSOC.Further,the evident negative correlation between MAE365 and OPDTT was observed.Our results showed coconut biodiesel/diesel blends soot induced lower levels of oxidative potential,whereas absorption of light was higher,which have far reaching consequences on climate forcing.Therefore,it is important to evaluate the balance point between light-absorbing properties and oxidative potential,under the wide use of biodiesel. 展开更多
关键词 Soot particle BIODIESEL Light absorption Mass absorbing efficiency Oxidative potential Dithiothreitol(DTT)
Transient expression of SbDhr2 and MeHNL in Gossypium hirsutum for herbivore deterrence assay with Spodoptera litura 预览
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作者 MAHAJAN Chavi NASER Rafiuddin GUPTA Shantikumar 《棉花研究(英文)》 2020年第1期1-12,共12页
Background:Spodoptera litura(Lepidoptera:Noctuidae),commonly known as tobacco cutworm or cotton leafworm,is a polyphagous pest which causes considerable damage to cotton(Gossypium hirsutum)and other crops.Herbivore-in... Background:Spodoptera litura(Lepidoptera:Noctuidae),commonly known as tobacco cutworm or cotton leafworm,is a polyphagous pest which causes considerable damage to cotton(Gossypium hirsutum)and other crops.Herbivore-induced defence response is activated in plants against chewing pests,in which plant secondary metabolites play an important role.Dhurrinase2(SbDhr2),a cyanogenicβ-glucosidase from Sorghum bicolor,is the key enzyme responsible for the hydrolysis of dhurrin(cyanogenicβ-glucosidic substrate)to phydroxymandelonitrile.Hydroxynitrile lyase(Me HNL)from Mannihot esculanta catalyses the dissociation of cyanohydrins to hydrogen cyanide and corresponding carbonyl compound,both enzymes play a pivotal role in plant defence mechanism.Results:SbDhr2 and Me HNL genes were expressed individually and co-expressed transiently in cotton leaves.We examined the feeding response of S.litura to leaves in the choice assay.The S.litura population used in this study showed better feeding deterrence to leaves co-expressing both genes compared with the expression of an individual gene.Conclusion:Our results suggest that co-expression of SbDhr2 and Me HNL genes in cotton leaves demonstrate feeding deterrence to S.litura.Engineering cyanogenic pathway in aerial parts of cotton would be an additional defence strategy against generalist pests and can be enhanced against specialist pests. 展开更多
关键词 SbDhr2 MeHNL HCNc(hydrogen cyanide concentration) HCNp(hydrogen cyanide potential) TRV(tobacco rattle virus) Spodoptera litura Plant defence
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Ro-vibrational Spectra of the Simplest Deuterated Criegee Intermediate CD2OO 预览
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作者 Jun Li 《化学物理学报》 SCIE CAS CSCD 2020年第1期65-68,共4页
Criegee intermediates are of signi cance in the atmospheric chemistry.In this work,the rovibrational spectra of the simplest deuterated Criegee intermediate,CD2OO,were studied by a vibrational self-consistent eld/virt... Criegee intermediates are of signi cance in the atmospheric chemistry.In this work,the rovibrational spectra of the simplest deuterated Criegee intermediate,CD2OO,were studied by a vibrational self-consistent eld/virtual con guration interaction(VSCF/VCI)method based on a nine-dimensional accurate potential energy surface and dipole surface for its ground electronic state.The calculated fundamental vibrational frequencies and rotational constants are in excellent agreement with the available experimental results.These data are useful for further spectroscopic studies of CD2OO.Especially,the rotational constants for excited vibrational levels are essential for experimental spectral assignments.However,the infrared intensities from di erent resources,including the current computation,the experiment,and previous calculations at the NEVPT2 and B3LYP levels,deviate signi cantly. 展开更多
关键词 Criegee intermediates Vibrational spectra Rotational constants Multimode calculations Potential energy surface
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低效油井治理效益潜力模糊综合评价 预览
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作者 郭福军 《海洋石油》 CAS 2020年第1期61-64,69,共5页
油田进入开发中后期低效井呈逐年上升的趋势,低效井综合治理工作是油田需要开展的主要工作,如何保证低效井的治理具有效益是老油田开发面临的主要问题。为了提高低效油井的治理效果和老油田开发整体效益,以油田单井效益评价系统为依托,... 油田进入开发中后期低效井呈逐年上升的趋势,低效井综合治理工作是油田需要开展的主要工作,如何保证低效井的治理具有效益是老油田开发面临的主要问题。为了提高低效油井的治理效果和老油田开发整体效益,以油田单井效益评价系统为依托,从单井入手,探索适合低效井治理效益潜力的评价标准、方法与指标体系。通过低效油井治理效益潜力评价体系的构建,采用模糊综合评价对57口低效油井进行效益潜力综合评价,降低了油井治理措施实施的风险,提高了低效油井治理的成功率和治理效果。现场实际应用表明,模糊综合评价可以提高油井效益潜力评价的客观性、准确性,具有较强的实用性和可操作性。 展开更多
关键词 低效油井 效益 潜力 模糊综合评价
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Ground state properties and potential energy surfaces of 270Hs from multidimensionally-constrained relativistic mean field model
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作者 Xu Meng BingNan Lu ShanGui Zhou 《中国科学:物理学、力学、天文学英文版》 SCIE EI CAS CSCD 2020年第1期70-80,共11页
We study the ground state properties,potential energy curves and potential energy surfaces of the superheavy nucleus 270Hs by using the multidimensionally-constrained relativistic mean-field model with the efFective i... We study the ground state properties,potential energy curves and potential energy surfaces of the superheavy nucleus 270Hs by using the multidimensionally-constrained relativistic mean-field model with the efFective interaction PC-PK1.The binding energy,size and shape as well as single particle shell structure corresponding to the ground state of this nucleus are obtained.270Hs is well deformed and exhibits deformed doubly magic feature in the single neutron and proton level schemes.One-dimensional potential energy curves and two-dimensional potential energy surfaces are calculated for 270Hs with various spatial symmetries imposed.We investigate in detail the effects of the reflection asymmetric and tri axial distortions on the fission barrier and fission path of 270Hs.When the axial symmetry is imposed,the reflection symmetric and reflection asymmetric fission barriers both show a double-hump structure and the former is highe匚However,when tri axial shapes are allowed the reflection symmetric barrier is lowered very much and then the reflection symmetric fission path becomes favorable. 展开更多
关键词 MDC-RMF model superheavy nuclei potential energy surface fission barrier reflection asymmetry triaxial deformation
A look into the past,present and future potential distributions of Talinopsis frutescens,a North American endemic lineage closely related to Cactaceae 预览
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作者 Mónica I MIGUEL-VÁZQUEZ Yasser S LÓPEZ DE OLMOS R Gilberto OCAMPO 《干旱区科学:英文版》 SCIE CSCD 2020年第1期104-114,共11页
Talinopsis frutescens(Anacampserotaceae,a family that is close related to Cactaceae)is a succulent species endemic to North America.The aim of this study was to explore,using Ecological Niche Modeling(ENM),changes in ... Talinopsis frutescens(Anacampserotaceae,a family that is close related to Cactaceae)is a succulent species endemic to North America.The aim of this study was to explore,using Ecological Niche Modeling(ENM),changes in potential distribution ranges considering different climate scenarios:past conditions during the Last Inter Glacial(LIG)and the Last Glacial Maximum(LGM),the present and projections for 2070(RCP 2.6 to 8.5).A pattern of contraction is observed during the LIG,which agrees with other studies focused in species from arid environments.This pattern was followed by a migration towards the south during the LGM and a possible recent expansion to the north as is observed in the present scenario.All future projections show the same contraction and fragmentation patterns,resulting in three discontinuous areas:the northern part of the Chihuahuan Desert,the southern-central part of the Mexican Plateau,and the smallest one in the Tehuacán-Cuicatlán Valley.Our projections for future scenarios agree with other studies and support that global climate change tends to alter the current distribution of arid environment species. 展开更多
关键词 Anacampserotaceae Caryophyllales ecological niche modeling succulent plants potential distribution
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Management of Colorado potato beetle in invasive frontier areas 预览
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作者 WANG Cong XU Han PAN Xu-bin 《农业科学学报:英文版》 SCIE CAS CSCD 2020年第2期360-366,共7页
Colorado potato beetle(CPB)is one of the most devastating invasive insects and it is native to North America.It feeds on several wild species of the genus Solamum,such as S.elaeagnifolium and S.rostratum Dunal,and is ... Colorado potato beetle(CPB)is one of the most devastating invasive insects and it is native to North America.It feeds on several wild species of the genus Solamum,such as S.elaeagnifolium and S.rostratum Dunal,and is one of the major pests of potato and eggplant.Beginning in the early 19 th century,CPB has rapidly spread across North America,Europe,and Central Asia.CPB was first reported to invade Xinjiang of China in 1993 and it was effectively controlled in Mori County.Since 2013,CPB has also been found in Jilin and Heilongjiang in Northeast China,and it likely migrated to these provinces from Russia.Thus,China has become the frontier for the global CPB spread,and risk management and monitoring systems for this pest are urgently needed.Here,we summarize pest management methods that are used in areas at the frontier of the CPB invasion,and put forward frameworks for further preventing and controlling of the spread of CPB.The management methods for CPB can also serve as an example for the control of invasive species mitigation in frontier areas. 展开更多
关键词 potential geographical distribution monitoring strategies host management
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