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Masseter Vestibular evoked myogenic potentials: A new tool to assess the vestibulomasseteric reflex pathway
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作者 Aishwarya Nagarajan Sujeet Kumar Sinha 《Journal of Otology》 CAS CSCD 2024年第1期46-54,共9页
Purpose: This review article provides the readers with an in-depth insight in understanding and interpreting various research literatures on the masseter vestibular evoked myogenic potentials(mVEMP). The article also ... Purpose: This review article provides the readers with an in-depth insight in understanding and interpreting various research literatures on the masseter vestibular evoked myogenic potentials(mVEMP). The article also reviews the contemporary researches involving the clinical applications of the mVEMP. Conclusions: Masseter VEMP is an evolving yet clinically promising neuro-otology test tool that has recently gained more research interest and is considered an additional tool to diagnose various vestibular disorders. Masseter VEMP assesses the functional integrity of the acoustic-masseteric and vestibulo-masseteric reflex pathways. The mVEMP could be used as a complementary test to evaluate the same peripheral generator as the cervical VEMP but a different central pathway i.e., vestibulo-trigeminal pathway. Various research studies that have experimented on parameters such as the effect of different electrode montages(zygomatic vs mandibular configurations), stimulation rates, filter settings and stimuli used to evoke mVEMP have been discussed in this article that could assist in the optimization of a comprehensive clinical protocol. The latency and the amplitude of mVEMP waveforms serve as significant parameters in differentiating normals from those of the clinical populations. Along with the cVEMPs and oVEMPs, mVEMP might help diagnose brainstem lesions in REM Sleep behaviour disorders, Multiple Sclerosis and Parkinson's disease. However, further studies are required to probe in this area of research. 展开更多
关键词 Masseter vestibular evoked myogenic potentials(mvemp) Vestibulo-masseteric pathway Acoustic-masseteric pathway
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Mass Increase with Strong and Gravitational Potentials, and Mass Defect with Electromagnetic Potential
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作者 Hany Ali Hussein 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第3期1079-1094,共16页
The proposal is “mass increases due to strong and gravitational potentials, while it decreases due to Electromagnetic potential”. This proposal explains the big difference in mass between hadrons (protons, neutrons,... The proposal is “mass increases due to strong and gravitational potentials, while it decreases due to Electromagnetic potential”. This proposal explains the big difference in mass between hadrons (protons, neutrons, & mesons) and their components (quarks), mass difference between nucleus and its individual components (protons and neutrons), massless of gamma photons, abnormal masses of mesons and bosons, and the excess in galaxy masses (dark matter). Also, this proposal shows the exact relation between mass and energy: Strong Potential=−3.04mc2| Electric Potential |=−5.57×10−3mc2Gravitational Potential=−1.22×10−7mc2where m represents the excess in mass due to strong potential, or gravitational potential and represents the decrease in mass due to electromagnetic potential. Released energy here equals potential energy and doesn’t equal decrease in mass using the formula E = mc2. Released energy is transferred to heat, photons, kinetic energy… Finally, proposal will try to describe the relation between photon energy and mass of its components using the general equation of kinetic energy: Photon Energy=1/2mc2m is the sum of the individual masses of its components, while the total mass of photon is zero. 展开更多
关键词 Mass Defect Dark Matter PHOTON Gamma Photon Strong Potential Gravitational Potential Electromagnetic Potential QUARKS Mesons BOSONS Deuterium Proton Neutron
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Median Nerve Somatosensory Evoked Potentials in Patients with Chiari Malformation
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作者 Mustafa Harun Sahin Gonul Vural +1 位作者 Serdar Barakli Sadiye Gumusyayla 《World Journal of Neuroscience》 CAS 2024年第1期24-32,共9页
Abnormal SEP reflects dysfunction of the medial lemniscus and posterior cervical cord. These structures are likely to be affected in Chiari malformation. Therefore, SEP abnormalities may provide valuable information i... Abnormal SEP reflects dysfunction of the medial lemniscus and posterior cervical cord. These structures are likely to be affected in Chiari malformation. Therefore, SEP abnormalities may provide valuable information in patients with CM. However, the consistency of SEP abnormality or normality with the damage is a matter of research. Knowing whether median nerve somatosensory evoked potential (SEP) is useful in revealing subclinical damage in patients with Chiari malformation is important in the treatment and follow-up plan of the disease. The aim of this study was to investigate the relationship between median nerve SEP values and the severity of cerebellar ectopia in patients with Chiari type 1 malformation. Median nerve SEP values were obtained from 30 healthy individuals and 146 individuals with Chiari malformation. The cerebellar ectopia degree and McRae line length were measured. SEP values were not significantly different between groups. The McRae line was found to be significantly shorter in the control group than in the Chiari malformation group (p = 0.031). There was no correlation between the degree of cerebellar ectopia and the length of the McRae line (r = 0.002, p = 0.979). Neither cerebellar ectopy degree nor McRae line length had a relationship with SEP values (r = -0.153, p = 0.066;r = -0.056, p = 0.500, respectively). There was no difference in cerebellar ectopy degree or SEP values between the groups with cerebellar ectopy with and without a syrinx (p = 0.899;p = 0.080, respectively). Likewise, McRae line length was not found to be related to the presence of a syrinx (p = 0.139). Median nerve SEP examination was not beneficial for diagnosing asymptomatic-oligosymptomatic Chiari malformation as a subclinical injury, whether accompanied by syringomyelia or not. 展开更多
关键词 Chiari Malformation Cerebellar Ectopy Somatosensory Evoked Potential
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Thermal conductivity of GeTe crystals based on machine learning potentials
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作者 张健 张昊春 +1 位作者 李伟峰 张刚 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期104-107,共4页
GeTe has attracted extensive research interest for thermoelectric applications.In this paper,we first train a neuroevolution potential(NEP)based on a dataset constructed by ab initio molecular dynamics,with the Gaussi... GeTe has attracted extensive research interest for thermoelectric applications.In this paper,we first train a neuroevolution potential(NEP)based on a dataset constructed by ab initio molecular dynamics,with the Gaussian approximation potential(GAP)as a reference.The phonon density of states is then calculated by two machine learning potentials and compared with density functional theory results,with the GAP potential having higher accuracy.Next,the thermal conductivity of a GeTe crystal at 300 K is calculated by the equilibrium molecular dynamics method using both machine learning potentials,and both of them are in good agreement with the experimental results;however,the calculation speed when using the NEP potential is about 500 times faster than when using the GAP potential.Finally,the lattice thermal conductivity in the range of 300 K-600 K is calculated using the NEP potential.The lattice thermal conductivity decreases as the temperature increases due to the phonon anharmonic effect.This study provides a theoretical tool for the study of the thermal conductivity of GeTe. 展开更多
关键词 machine learning potentials thermal conductivity molecular dynamics
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Clinical characteristics and analysis of vestibular-evoked myogenic potentials in patients with sudden sensorineural hearing loss in different ages
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作者 Yan-Zhuo Zhang Ya-Bo Wang +6 位作者 Jing-Lei Fang Yue-Tang Wang Gui-Fang Li Ran-Ran Liu Shu-Jing Shi Chun-Hua Wang Yong-Tao Tian 《World Journal of Clinical Cases》 SCIE 2024年第19期3760-3766,共7页
BACKGROUND Numerous studies have found that patients experiencing sudden sensorineural hearing loss(SSHL),with or without accompanying vertigo,often show impaired vestibular function.However,there is a dearth of studi... BACKGROUND Numerous studies have found that patients experiencing sudden sensorineural hearing loss(SSHL),with or without accompanying vertigo,often show impaired vestibular function.However,there is a dearth of studies analyzing vestibularevoked myogenic potentials(VEMPs)in SSHL patients across various age groups.AIM To investigate vestibular condition in SSHL patients across various age demographics.METHODS Clinical data of 84 SSHL patients were investigated retrospectively.Audiometry,cervical vestibular evoked myogenic potentials(c-VEMPs),and ocular vestibular evoked myogenic potentials(o-VEMPs)were conducted on these patients.Parameters assessed included the latencies of P1 and N1 waves,as well as the amplitudes of P1–N1 waves.Moreover,the study evaluated the influence of factors such as sex,affected side,configuration of hearing loss,and presence of accompanying vertigo.RESULTS Among the 84 SSHL patients,no significant differences were observed among the three groups in terms of gender,affected side,and the presence or absence of vertigo.Group II(aged 41–60 years)had the highest number of SSHL cases.The rates of absent o-VEMPs in the affected ears were 20.83%,31.58%,and 22.72%for the three age groups,respectively,with no statistically significant difference among them.The rates of absent c-VEMPs in the affected ears were 8.3%,34.21%,and 18.18%for the three age groups,respectively,with significant differences.In the unaffected ears,there were differences observed in the extraction rates of o-VEMPs in the unaffected ears among the age groups.In the three age groups,no significant differences were noted in the three age groups in the latencies of P1 and N1 waves or in the amplitude of N1–P1 waves for c-VEMPs and o-VEMPs,either on the affected side or on the unaffected side,across the three age groups.CONCLUSION The extraction rate of VEMPs is more valuable than parameters.Regardless of the presence of vertigo,vestibular organs are involved in SSHL.Notably,SSHL patients aged 41–60 appear more susceptible to damage to the inferior vestibular nerve and saccule. 展开更多
关键词 Sudden sensorineural hearing loss Cervical vestibular evoked myogenic potential Ocular vestibular evoked myogenic potential VERTIGO Pure tone audiometry
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Tetrathiafulvalene esters with high redox potentials and improved solubilities for non-aqueous redox flow battery applications
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作者 Weikang Hu Jiaqi Xu +3 位作者 Nanjie Chen Zongcai Deng Yuekun Lai Dongyang Chen 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第5期899-908,共10页
The exploitation of high performance redox-active substances is critically important for the development of non-aqueous redoxflow batteries.Herein,three tetrathiofulvalene(TTF)derivatives with different substitution gr... The exploitation of high performance redox-active substances is critically important for the development of non-aqueous redoxflow batteries.Herein,three tetrathiofulvalene(TTF)derivatives with different substitution groups,namely TTF diethyl ester(TTFDE),TTF tetramethyl ester(TTFTM),and TTF tetraethyl ester(TTFTE),are prepared and their energy storage properties are evaluated.It has been found that the redox potential and solubility of these TTF derivatives in conventional carbonate electrolytes increases with the number of ester groups.The battery with a catholyte of 0.2 mol L^(-1) of TTFTE delivers a specific capacity of more than 10 Ah L^(-1) at the current density of 0.5 C with two discharge voltage platforms locating at as high as 3.85 and 3.60 V vs.Li/Liþ.Its capacity retention can be improved from 2.34 Ah L^(-1) to 3.60 Ah L^(-1) after 100 cycles by the use of an anion exchange membrane to block the crossover of TTF species.The excellent cycling stability of the TIF esters is supported by their well-delocalized electrons,as revealed by the density function theory calculations.Therefore,the introduction of more and larger electron-withdrawing groups is a promising strategy to simultaneously increase the redox-potential and solubility of redox-active ma-terials for non-aqueous redoxflow batteries. 展开更多
关键词 Non-aqueous redox flow batteries Tetrathiofulvarene Redox potential SOLUBILITY Substituent effect
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Entrepreneurship training:its influences on innovation potentials among nursing students
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作者 Asmaa Abdel Rahman Abdel Rahman Dalia Abdallah Abdelatief 《Frontiers of Nursing》 2024年第1期85-98,共14页
Objective:To evaluate the influences of entrepreneurship training on the innovation potential among nursing students.Methods:A quasi-experimental design was utilized to conduct this study.The study was conducted in th... Objective:To evaluate the influences of entrepreneurship training on the innovation potential among nursing students.Methods:A quasi-experimental design was utilized to conduct this study.The study was conducted in the classroom at the faculty of nursing,and the“i Hub”center at Ain Shams University(ASU)in Cairo,Egypt.A purposive sample of 42 nursing students who participated in the“Ain Shams University-innovate”competition from the Faculty of Nursing of ASU were included in this study.Data collection tools included(1)Nursing students'innovation skills assessment questionnaire and(2)Innovative projects evaluation tool.Results:There was a statistically significant difference between the mean scores of nursing students'total innovation skills pre-and post-implementation of entrepreneurship training,where P-value<0.05.Conclusions:The results of the current study support the research hypothesis because the implementation of entrepreneurship training positively affects nursing students'innovation potential.Developing entrepreneurship education in nursing and integrating it into nursing programs will stimulate creativity,innovation,and entrepreneurship among nursing students and health care services. 展开更多
关键词 entrepreneurship training innovation potentials nursing students creative skills energy/motivation
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Theoretical uncertainties of(d,^(3)He)and(^(3)He,d)reactions owing to the uncertainties of optical model potentials 被引量:2
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作者 Wei-Jia Kong Dan-Yang Pang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第6期147-153,共7页
The theoretical uncertainties of single proton transfer cross sections of the(^(3)He,d)and(d,^(3)He)reactions,owing to the uncertainties of the entrance-and exit-channel optical model potentials,are examined with the^... The theoretical uncertainties of single proton transfer cross sections of the(^(3)He,d)and(d,^(3)He)reactions,owing to the uncertainties of the entrance-and exit-channel optical model potentials,are examined with the^(30)Si(^(3)He,d)^(31)P,^(13)B(d,^(3)He)^(12)Be,and^(34)S(^(3)He,d)^(35)Cl reactions at incident energies of 25,46,and 25 MeV,respectively,within the framework of the distorted wave Born approximation.The differential cross sections at the first peaks in the angular distributions of these reactions are found to have uncertainties of approximately 5%,owing to the uncertainties in the optical model potentials from 20,000 calculations of randomly sampled parameters.This amount of uncertainty is found to be nearly independent of the angular momentum transfer and the target masses within the studied range of incident energies.Uncertainties in the single proton spectroscopic factors obtained by matching the theoretical and experimental cross sections at different scattering angles are also discussed. 展开更多
关键词 Proton transfer reactions Optical model potentials Spectroscopic factors
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Identification of injury type using somatosensory and motor evoked potentials in a rat spinal cord injury model 被引量:1
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作者 Rong Li Han-Lei Li +2 位作者 Hong-Yan Cui Yong-Can Huang Yong Hu 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第2期422-427,共6页
The spinal cord is at risk of injury during spinal surgery.If intraoperative spinal co rd injury is identified early,irreve rsible impairment or loss of neurological function can be prevented.Different types of spinal... The spinal cord is at risk of injury during spinal surgery.If intraoperative spinal co rd injury is identified early,irreve rsible impairment or loss of neurological function can be prevented.Different types of spinal cord injury result in damage to diffe rent spinal cord regions,which may cause diffe rent somatosensory and motor evoked potential signal res ponses.In this study,we examined electrophysiological and histopathological changes between contusion,distra ction,and dislocation spinal cord injuries in a rat model.We found that contusion led to the most severe dorsal white matter injury and caused considerable attenuation of both somatosensory and motor evoked potentials.Dislocation resulted in loss of myelinated axons in the lateral region of the injured spinal cord along the rostrocaudal axis.The amplitude of attenuation in motor evoked potential responses caused by dislocation was greater than that caused by contusion.After distraction injury,extracellular spaces were slightly but not significantly enlarged;somatosensory evoked potential res ponses slightly decreased and motor evoked potential responses were lost.Correlation analysis showed that histological and electrophysiological findings we re significantly correlated and related to injury type.Intraope rative monitoring of both somatosensory and motor evoked potentials has the potential to identify iatrogenic spinal cord injury type during surgery. 展开更多
关键词 contusion injury dislocation injury distraction injury electropnysiology heterogeneity HISTOPATHOLOGY injury mechanism motor evoked potential somatosensory evoked potential spinal cord injury
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Similarity of Binding Potentials Between Plant DUF538 and Animal Lipocalin: Cholesterol Binding Ability of DUF538
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作者 Ashraf GHOLIZADEH 《生物化学与生物物理进展》 SCIE CAS CSCD 北大核心 2023年第2期371-384,共14页
Objective DUF538(domain of unknown function 538) domain containing proteins are known as putative hypothetical proteins in plants. Until yet, there is no much information regarding their structure and function. Method... Objective DUF538(domain of unknown function 538) domain containing proteins are known as putative hypothetical proteins in plants. Until yet, there is no much information regarding their structure and function. Methods In the present research work, the homologous structures and binding potentials were identified between plant/mammalian lipocalins and plant DUF538 protein by using bioinformatics and experimental tools including molecular dynamics simulation, molecular docking and recombinant technology-based techniques. Results Molecular docking analysis of their interactions with lipidic ligands including cholesterol and palmitic acid revealed the similar and comparable binding potentials between DUF538 and lipocalin proteins. Both the test proteins were found to have more affinity to cholesterol molecule in compare to palmitic acid. By using recombinant technology-based experiments, the heterologously expressed and purified fused product of DUF538 protein exhibited about 61% cholesterol binding ability. Conclusion As a conclusion, plants DUF538 protein family was predicted to be the structural and may be the functional homologues of plants/animals lipocalin superfamily. 展开更多
关键词 binding potential CHOLESTEROL DUF538 lipocalin palmitic acid
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改进A^(*)算法和人工势场法的路径规划 被引量:10
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作者 余翔 姜陈 +1 位作者 段思睿 邓千锐 《系统仿真学报》 CAS CSCD 北大核心 2024年第3期782-794,共13页
A^(*)算法存在折线路径多和搜索节点多的问题,人工势场(artificial potential field,APF)法存在局部最优和不可到达的问题,针对两种算法存在的问题进行了研究。利用欧氏距离与投影距离提出一种新的混合式启发函数,依据该函数对A^(*)算... A^(*)算法存在折线路径多和搜索节点多的问题,人工势场(artificial potential field,APF)法存在局部最优和不可到达的问题,针对两种算法存在的问题进行了研究。利用欧氏距离与投影距离提出一种新的混合式启发函数,依据该函数对A^(*)算法的流程进行改进,减少A^(*)算法的搜索节点,提高搜索效率。利用新A^(*)算法生成的最优节点作为APF算法的局部目标点,辅助机器人摆脱局部最优点;通过加入机器人和目标点的位置关系改进势场函数,修改斥力的增益,优化斥力的生成方向。在改进的基础上将两种算法融合提出一种新的算法,利用APF法的势场函数引导A^(*)算法的搜索。从路径长度、避障效果、迭代次数对改进算法进行对比分析,仿真结果表明,提出的改进算法搜索效率高,实现避障的同时保证计算的路径最优。 展开更多
关键词 APF算法 A^(*)算法 路径规划 引力势场 斥力势场
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THE ANALYTIC SMOOTHING EFFECT OF LINEAR LANDAU EQUATION WITH SOFT POTENTIALS
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作者 李浩光 徐超江 《Acta Mathematica Scientia》 SCIE CSCD 2023年第6期2597-2614,共18页
In this work,we study the linearized Landau equation with soft potentials and show that the smooth solution to the Cauchy problem with initial datum in L^(2)(ℝ^(3))enjoys an analytic regularization effect,and that the... In this work,we study the linearized Landau equation with soft potentials and show that the smooth solution to the Cauchy problem with initial datum in L^(2)(ℝ^(3))enjoys an analytic regularization effect,and that the evolution of the analytic radius is the same as the heat equations. 展开更多
关键词 linear Landau equation analytic smoothing effect soft potential
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A Class of Potentials for Hyperbolic Transcendental Entire Maps
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作者 Irene Inoquio-Renteria 《Advances in Pure Mathematics》 2023年第8期483-494,共12页
We identify a class of transcendental entire maps of finite order, of disjoint-type, satisfying the rapid derivative growth condition. Within this class, we show that there exist hyperbolic transcendental entire maps ... We identify a class of transcendental entire maps of finite order, of disjoint-type, satisfying the rapid derivative growth condition. Within this class, we show that there exist hyperbolic transcendental entire maps that generate a large class of potentials which intersect the so-called tame potentials and form a distinct class of potentials. The methods and techniques derived from the thermodynamic formalism are applied to these potentials for transcendental entire maps acting on some subset of the Julia set which is conjugated to the shift map over a code space with a countable alphabet endowed with the euclidean induced metric on the complex plane. 展开更多
关键词 Thermodynamic Formalism Entire Transcendental Functions Tame potentials
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A Study of Compound Action Potentials in Current-Coupled Tracts: the General Case
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作者 Aman Chawla Salvatore Domenic Morgera 《Journal of Applied Mathematics and Physics》 2023年第11期3345-3353,共9页
In this paper, the authors investigate compound action potentials formed when the underlying tract's axons have current-mediated coupling amongst themselves, and no field-mediated coupling. The key finding of the ... In this paper, the authors investigate compound action potentials formed when the underlying tract's axons have current-mediated coupling amongst themselves, and no field-mediated coupling. The key finding of the paper is that, for the case of biophysically inhomogeneous axon tracts, the compound action potential is governed by a Hodgkin-Huxley like equation itself in certain cases. The paper extends an earlier result for the identical axon case. 展开更多
关键词 Compound Action potentials Current-Mediated Coupling Biophysically Inhomogeneous Axon Tracts Hodgkin-Huxley Equation Identical Axon Case
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水基炭黑-胶原蛋白纳米流体制备及稳定性实验 被引量:2
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作者 李凯 魏鹤琳 +3 位作者 左夏华 杨卫民 阎华 安瑛 《化工进展》 EI CAS CSCD 北大核心 2024年第4期1944-1952,共9页
纳米流体由于其优异的光热转换性能,已成为新型太阳能集热介质的研究重点;但因其稳定性差、制备工艺复杂,未能在实际应用中得到推广。本文以去离子水为基液,通过两步法制备炭黑-胶原蛋白纳米流体。探究了材料添加顺序、胶原蛋白种类、... 纳米流体由于其优异的光热转换性能,已成为新型太阳能集热介质的研究重点;但因其稳定性差、制备工艺复杂,未能在实际应用中得到推广。本文以去离子水为基液,通过两步法制备炭黑-胶原蛋白纳米流体。探究了材料添加顺序、胶原蛋白种类、超声时间、材料配比以及溶液pH等对纳米流体稳定性的影响。结果表明,制备水基炭黑-胶原蛋白纳米流体时,先分散炭黑再加入胶原蛋白可以提高其稳定性;猪皮胶原蛋白更适用于炭黑-胶原蛋白纳米流体的制备;超声45min,炭黑胶原蛋白质量配比为1/20,悬浮液pH在6.5~7.5之间制备得到的纳米流体稳定性较好。本研究有助于今后水基炭黑-胶原蛋白纳米流体产业化应用于太阳能光热转换领域。 展开更多
关键词 纳米流体 炭黑 胶原蛋白 稳定性 分光光度计法 ZETA电位
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新能源汽车碳减排潜力分析 被引量:7
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作者 王震坡 詹炜鹏 +3 位作者 孙逢春 邓钧君 崔丁松 黎小慧 《北京理工大学学报》 EI CAS CSCD 北大核心 2024年第2期111-122,共12页
在“碳达峰、碳中和”双碳目标驱动下,新能源汽车凭借其碳减排优势受到了广泛关注.旨在促进新能源汽车碳减排潜力评估的相关研究,从新能源汽车碳排放计量与分析、车网协同优化低碳运行、车辆碳排放总量态势预测等三个方面进行分析与综述... 在“碳达峰、碳中和”双碳目标驱动下,新能源汽车凭借其碳减排优势受到了广泛关注.旨在促进新能源汽车碳减排潜力评估的相关研究,从新能源汽车碳排放计量与分析、车网协同优化低碳运行、车辆碳排放总量态势预测等三个方面进行分析与综述,归纳了相关领域最新研究成果,总结各类建模方法优缺点,重点阐述了汽车节能减排核算体系与行业碳排放管理体系等相关成果,并提出新能源汽车碳减排潜力分析研究的发展趋势及未来研究方向. 展开更多
关键词 新能源汽车 碳排放 减排潜力
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黑土地保护视角下黑龙江省畜禽养殖环境效应分析 被引量:1
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作者 姜冰 康祎梅 +1 位作者 李全峰 王晨 《农业资源与环境学报》 CAS CSCD 北大核心 2024年第3期592-605,共14页
为合理利用畜禽粪污资源,保护黑龙江省黑土地资源,优化农畜业生产布局,实现农牧业绿色发展,本研究基于2011—2020年统计数据及文献资料,测算了黑龙江省畜禽粪污排放情况,并据此分析黑龙江省畜禽粪污资源化利用潜力及畜禽养殖环境承载力... 为合理利用畜禽粪污资源,保护黑龙江省黑土地资源,优化农畜业生产布局,实现农牧业绿色发展,本研究基于2011—2020年统计数据及文献资料,测算了黑龙江省畜禽粪污排放情况,并据此分析黑龙江省畜禽粪污资源化利用潜力及畜禽养殖环境承载力。结果表明:从时间动态来看,2011—2020年,黑龙江省畜禽粪尿、粪尿养分、COD排放量均有小幅下降,降幅分别为3.68%、3.24%和5.82%;畜禽粪污的化肥替代潜力虽整体略有下降,但10年来均保持在35%以上,2020年化肥替代潜力已达到41.89%,具有较高的有机肥替代化肥潜力;黑龙江省畜禽粪污的能源潜力略有增长,但对煤炭的替代潜力呈下降趋势且替代作用并不显著,2020年畜禽粪污的沼气潜力为46.74亿m^(3),折合为标准煤仅占标准煤消费量的2.90%,能源潜力有待进一步开发利用;黑龙江省畜禽粪尿、粪尿氮、粪尿磷的耕地负荷均未超载,无养殖环境风险,畜禽养殖环境容量的空间剩余呈上升趋势,剩余约2/3,以氮为基准计算,余量为13006.13万头猪当量,以磷为基准计算,余量为8463.19万头猪当量,具有较大养殖潜力。从空间分布来看,黑龙江省各地区畜禽粪污排放及资源化利用潜力存在明显差异,哈尔滨市、齐齐哈尔市、绥化市、大庆市以及佳木斯市等畜禽养殖集聚区的畜禽粪尿资源丰富,畜禽粪污的替代化肥潜力、能源潜力及畜禽养殖发展潜力较大。 展开更多
关键词 畜禽粪尿 资源化利用 替代化肥潜力 能源潜力 环境承载力 黑土地保护
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ChatGPT技术在生物医药领域的应用潜力与风险 被引量:2
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作者 王茜 李东巧 刘细文 《中国科学基金》 CSSCI CSCD 北大核心 2024年第1期200-210,共11页
本文系统梳理了ChatGPT的发展历程与现状,分析ChatGPT技术与生物医药领域的耦合情况。从知识创新与模型创新两个维度,划分生物医药领域ChatGPT技术应用的类型,并分析其应用焦点、应用场景和特征;从科学研究与消费终端应用的角度阐述各项... 本文系统梳理了ChatGPT的发展历程与现状,分析ChatGPT技术与生物医药领域的耦合情况。从知识创新与模型创新两个维度,划分生物医药领域ChatGPT技术应用的类型,并分析其应用焦点、应用场景和特征;从科学研究与消费终端应用的角度阐述各项ChatGPT技术类型在生物医药领域中的应用价值;剖析各项ChatGPT技术类型在生物医药领域中存在的潜在风险。ChatGPT技术将加快生物医药领域的研究与服务,扩大而非取代研究人员的专业知识。未来应加强微调挖掘型GPT工具与部署型服务设施的建设,推动ChatGPT技术在生物医药领域的有效应用。 展开更多
关键词 ChatGPT 生物医药 应用场景 潜在风险 人工智能
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不同年龄段健听人颈性前庭诱发肌源性电位参数的研究 被引量:1
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作者 侯小娟 吴梅 +2 位作者 刘静 张伦 丁伟 《中国听力语言康复科学杂志》 2024年第1期61-64,共4页
目的探讨颈性前庭诱发肌源性电位在不同年龄段健听人群中的正常参考值范围。方法将60例健康志愿者分为儿童组和成人组,利用丹麦WDH集团的Eclipse客观听觉测试平台分别进行颈性前庭诱发肌源性电位测试,对数据进行统计学分析。结果两组中... 目的探讨颈性前庭诱发肌源性电位在不同年龄段健听人群中的正常参考值范围。方法将60例健康志愿者分为儿童组和成人组,利用丹麦WDH集团的Eclipse客观听觉测试平台分别进行颈性前庭诱发肌源性电位测试,对数据进行统计学分析。结果两组中左侧和右侧间P1、Nl潜伏期、P1-N1波间期、振幅、不对称比均无显著差异;两组中男性和女性间P1、Nl潜伏期、P1-N1波间期、振幅、不对称比均无显著差异;儿童组中P1正常值范围为13.97±1.46 ms,N1正常值范围为21.82±1.85 ms,振幅正常范围为100.71±91.17μV,波间期正常范围为7.85±1.12 ms;成人组中P1正常值范围为16.11±2.23 ms,N1正常值范围为24.66±2.35 ms,振幅正常范围为61.26±27.74μV,波间期正常范围为8.58±1.48 ms;两组之间P1、Nl潜伏期、P1-N1波间期、振幅均有显著差异(P<0.05),不对称比无显著差异。结论颈性前庭诱发肌源性电位的波形及参数与侧别、性别无相关性,潜伏期、波间期随年龄增长而延长,振幅随年龄的增长而减小。 展开更多
关键词 颈性 前庭诱发肌源性电位
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基于XGBoost算法的可恢复耕地宜耕性评价——以湘阴县为例 被引量:2
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作者 刘敏 周健 +4 位作者 胡月明 张林 赵清林 秦雅静 陈瑗瑗 《农业资源与环境学报》 CAS CSCD 北大核心 2024年第1期49-60,共12页
为科学有序开展可恢复耕地资源的整治,本研究提出一种基于XGBoost算法的可恢复耕地的宜耕性评价方法。选取自然条件、区位条件、社会经济状况以及工程条件等4个方面的因素,涉及海拔高程、坡度级别、国家自然等、集块面积、国家经济等、... 为科学有序开展可恢复耕地资源的整治,本研究提出一种基于XGBoost算法的可恢复耕地的宜耕性评价方法。选取自然条件、区位条件、社会经济状况以及工程条件等4个方面的因素,涉及海拔高程、坡度级别、国家自然等、集块面积、国家经济等、地块形状等36项影响因素为自变量,以现状可恢复耕地和耕种耕地二分类为因变量,分析各项影响因素对耕地宜耕性评价的重要程度,并进一步结合皮尔逊共线性分析和指标关联性分析,最终得到21项影响因素及其权重P值,优化后影响因素的权重P值相对稳定,其中自然因素对可恢复耕地宜耕性的影响权重最大,区位因素和工程因素权重次之,社会经济因素的权重最小。经过验证发现,预测耕种情况与实际耕种情况的符合率高达91.87%,且具有良好的泛化能力和鲁棒性,预测效果良好。借助上述模型预测得到的湘阴县可恢复耕地地块的宜耕潜力,形成如下认识:全县中西部平原区可恢复耕地宜耕潜力明显优于东部丘陵山区;可恢复耕地中未耕种和即可恢复地块的宜耕潜力高于工程恢复类地块,这些地块均属于良好的整治地块,可优先整治恢复为耕地;从可恢复耕地具体地类来看,坑塘和养殖坑塘类可恢复耕地的宜耕潜力最大,其次为其他林地类可恢复耕地;在耕地整治过程中,应结合可恢复耕地的宜耕性评价,合理有序地开展可恢复耕地的整治;此外,应开展精细化的耕地“非粮化”监测,实施差异化补偿政策,以遏制耕地“非粮化”。 展开更多
关键词 XGBoost 可恢复耕地 宜耕性 宜耕潜力 湘阴县
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