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Precise measurement of a weak radio frequency electric field using a resonant atomic probe 被引量:5
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作者 Liping Hao Yongmei Xue +3 位作者 Jiabei Fan Jingxu Bai Yuechun Jiao jianming zhao 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第3期164-168,共5页
We present a precise measurement of a weak radio frequency electric field with a frequency of ■3 GHz employing a resonant atomic probe that is constituted with a Rydberg cascade three-level atom, including a cesium g... We present a precise measurement of a weak radio frequency electric field with a frequency of ■3 GHz employing a resonant atomic probe that is constituted with a Rydberg cascade three-level atom, including a cesium ground state |6S(1/2)〉,an excited state |6P(3/2)〉, and Rydberg state |nD(5/2)〉. Two radio frequency(RF) electric fields, noted as local and signal fields, couple the nearby Rydberg transition. The two-photon resonant Rydberg electromagnetically induced transparency(Rydberg-EIT) is employed to directly read out the weak signal field having hundreds of k Hz difference between the local and signal fields that is encoded in the resonant microwave-dressed Rydberg atoms. The minimum detectable signal fields of ESmin= 1.36 ± 0.04 mV/m for 2.18 GHz coupling |68D(5/2)〉→ |69P(3/2)〉 transition and 1.33 ± 0.02 mV/m for 1.32 GHz coupling |80D(5/2)〉→ |81P(3/2)〉 transition are obtained, respectively. The bandwidth dependence is also investigated by varying the signal field frequency and corresponding -3 dB bandwidth of 3 MHz is attained. This method can be employed to perform a rapid and precise measurement of the weak electric field, which is important for the atom-based microwave metrology. 展开更多
关键词 RYDBERG electromagnetically induced transparency(Rydberg-EIT) ATOMIC PROBE WEAK field measurement
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Characteristic Insights on Industrial Cyber Security and Popular Defense Mechanisms 被引量:4
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作者 Ming Wan Jiawei Li +2 位作者 Ying Liu jianming zhao Jiushuang Wang 《China Communications》 SCIE CSCD 2021年第1期130-150,共21页
Due to the deep integration of information technology and operational technology,networked control systems are experiencing an increasing risk of international cyber attacks.In practice,industrial cyber security is a ... Due to the deep integration of information technology and operational technology,networked control systems are experiencing an increasing risk of international cyber attacks.In practice,industrial cyber security is a significant topic because current networked control systems are supporting various critical infrastructures to offer vital utility services.By comparing with traditional IT systems,this paper first analyzes the uncontrollable cyber threats and classified attack characteristics,and elaborates the intrinsic vulnerabilities in current networked control systems and novel security challenges in future Industrial Internet.After that,in order to overcome partial vulnerabilities,this paper presents a few representative security mechanisms which have been successfully applied in today’s industrial control systems,and these mechanisms originally improve traditional IT defense technologies from the perspective of industrial availability.Finally,several popular security viewpoints,adequately covering the needs of industrial network structures and service characteristics,are proposed to combine with burgeoning industrial information technologies.We target to provide some helpful security guidelines for both academia and industry,and hope that our insights can further promote in-depth development of industrial cyber security. 展开更多
关键词 industrial cyber threats industrial characteristics VULNERABILITIES security mechanisms and viewpoints
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Rydberg electromagnetically induced transparency and Autler–Townes splitting in a weak radio-frequency electric field 被引量:1
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作者 Liping Hao Yongmei Xue +3 位作者 Jiabei Fan Yuechun Jiao jianming zhao Suotang Jia 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第5期80-84,共5页
We utilize an electromagnetically induced transparency(EIT) of a three-level cascade system involving Rydberg state in a room-temperature cell, formed with a cesium 6 S_(1/2)–6 P_(3/2)–66 S_(1/2) scheme, to investig... We utilize an electromagnetically induced transparency(EIT) of a three-level cascade system involving Rydberg state in a room-temperature cell, formed with a cesium 6 S_(1/2)–6 P_(3/2)–66 S_(1/2) scheme, to investigate the Autler–Townes(AT)splitting resulting from a 15.21-GHz radio-frequency(RF) field that couples the |66 S_(1/2) → |65 P_(1/2) Rydberg transition.The radio-frequency electric field induced AT splitting, γAT, is defined as the peak-to-peak distance of an EIT-AT spectrum.The dependence of AT splitting γAT on the probe and coupling Rabi frequency, ?_p and ?_c, is investigated. It is found that the EIT-AT splitting strongly depends on the EIT linewidth that is related to the probe and coupling Rabi frequency in a weak RF-field regime. Using a narrow linewidth EIT spectrum would decrease the uncertainty of the RF field measurements.This work provides new experimental evidence for the theoretical framework in [J. Appl. Phys. 121, 233106(2017)]. 展开更多
关键词 RYDBERG electromagnetically induced transparency-Autler–Townes (EIT-AT) cascade FOUR-LEVEL atom RADIO-FREQUENCY (RF) electric field
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Dissecting the genome of star fruit(Averrhoa carambola L.) 被引量:2
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作者 Yannan Fan Sunil Kumar Sahu +11 位作者 Ting Yang Weixue Mu Jinpu Wei Le Cheng Jinlong Yang Ranchang Mu Jie Liu jianming zhao Yuxian zhao Xun Xu Xin Liu Huan Liu 《Horticulture Research》 SCIE 2020年第1期1626-1635,共10页
Averrhoa carambola is commonly known as star fruit because of its peculiar shape,and its fruit is a rich source of minerals and vitamins.It is also used in traditional medicines in countries such as India,China,the Ph... Averrhoa carambola is commonly known as star fruit because of its peculiar shape,and its fruit is a rich source of minerals and vitamins.It is also used in traditional medicines in countries such as India,China,the Philippines,and Brazil for treating various ailments,including fever,diarrhea,vomiting,and skin disease.Here,we present the first draft genome of the Oxalidaceae family,with an assembled genome size of 470.51 Mb.In total,24,726 protein-coding genes were identified,and 16,490 genes were annotated using various well-known databases.The phylogenomic analysis confirmed the evolutionary position of the Oxalidaceae family.Based on the gene functional annotations,we also identified enzymes that may be involved in important nutritional pathways in the star fruit genome.Overall,the data from this first sequenced genome in the Oxalidaceae family provide an essential resource for nutritional,medicinal,and cultivational studies of the economically important star-fruit plant. 展开更多
关键词 VITAMIN Brazil CULTIVATION
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Nonlinear spectroscopy of three-photon excitation of cesium Rydberg atoms in vapor cell 被引量:1
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作者 Jiabei Fan Yunhui He +3 位作者 Yuechun Jiao Liping Hao jianming zhao Suotang Jia 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第3期300-305,共6页
We present nonlinear spectra of four-level ladder cesium atoms employing 6 S1/2→6 P3/2→7 S1/2→30 P3/2 scheme of a room temperature vapor cell.A coupling laser drives Rydberg transition,a dressing laser couples two ... We present nonlinear spectra of four-level ladder cesium atoms employing 6 S1/2→6 P3/2→7 S1/2→30 P3/2 scheme of a room temperature vapor cell.A coupling laser drives Rydberg transition,a dressing laser couples two intermediate levels,and a probe laser optically probes the nonlinear spectra via electromagnetically induced transparency(EIT).Nonlinear spectra are detected as a function of coupling laser frequency.The observed spectra exhibit an enhanced absorption(EA) signal at coupling laser resonance to Rydberg transition and enhanced transmission(ET) signals at detunings to the transition.We define the enhanced absorption(transmission) strength,HEA(HET),and distance between two ET peaks,γET,to describe the spectral feature of the four-level atoms.The enhanced absorption signal HEA is found to have a maximum value when we vary the dressing laser Rabi frequency Ωd,corresponding Rabi frequency is defined as a separatrix point,ΩdSe.The values of ΩdSe and further η=ΩdSe/Ωc are found to depend on the probe and coupling Rabi frequency but not the atomic density.Based on ΩdSe,the spectra can be separated into two regimes,weak and strong dressing ranges,Ωd≤ΩdSe and Ωd≥QdSe,respectively.The spectroscopies display different features at these two regimes.A four-level theoretical model is developed that agrees well with the experimental results in terms of the probe-beam absorption behavior of Rabi frequency-dependent dressed states. 展开更多
关键词 nonlinear spectroscopy three-photon scheme Rydberg state
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Optoelectronic properties analysis of silicon light-emitting diode monolithically integrated in standard CMOS IC
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作者 Yanxu Chen Dongliang Xu +4 位作者 Kaikai Xu Ning Zhang Siyang Liu jianming zhao Qian Luo 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第10期115-120,共6页
Si p^+n junction diodes operating in the mode of avalanche breakdown are capable of emitting light in the visible range of 400-900 nm. In this study, to realize the switching speed in the GHz range, we present a trans... Si p^+n junction diodes operating in the mode of avalanche breakdown are capable of emitting light in the visible range of 400-900 nm. In this study, to realize the switching speed in the GHz range, we present a transient model to shorten the carrier lifetime in the high electric field region by accumulating carriers in both p and n type regions. We also verify the optoelectronic characteristics by disclosing the related physical mechanisms behind the light emission phenomena. The emission of visible light by a monolithically integrated Si diode under the reverse bias is also discussed. The light is emitted as spatial sources by the defects located at the p-n junction of the reverse-biased diode. The influence of the defects on the electrical behavior is manifested as a current-dependent electroluminescence. 展开更多
关键词 SILICON LIGHT-EMITTING DIODE REVERSE BIAS ELECTRO-OPTIC modulation
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Microwave Induced Ultralong-Range Charge Migration in a Rydberg Atom
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作者 Huihui Wang Yuechun Jiao +2 位作者 jianming zhao Liantuan Xiao Suotang Jia 《Chinese Physics Letters》 SCIE EI CAS CSCD 2022年第1期17-20,共4页
A microwave induced superposition of the 40S_(1/2) and 40P_(1/2) states of a Cs atom has been investigated in detail.Ultralong-range charge migration which spans a region more than 200 nm has been discovered. As far a... A microwave induced superposition of the 40S_(1/2) and 40P_(1/2) states of a Cs atom has been investigated in detail.Ultralong-range charge migration which spans a region more than 200 nm has been discovered. As far as we know, this is the first time to discover charge migration in such a long range. This leads to a large dipole moment which oscillates periodically. The present discovery may stimulate new applications such as quantum simulation of many body physics dominated by periodic interactions. In addition, we find an interesting phenomenon that Cs atoms in the superposition of 40S_(1/2) and 40P_(1/2) have a much larger blockade radius than those of Cs(40S_(1/2))or Cs(40P_(1/2)) atoms. 展开更多
关键词 SUPERPOSITION CHARGE RADIUS
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A Novel Deep Learning Representation for Industrial Control System Data
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作者 Bowen Zhang Yanbo Shi +2 位作者 jianming zhao Tianyu Wang Kaidi Wang 《Intelligent Automation & Soft Computing》 SCIE 2023年第6期2703-2717,共15页
Feature extraction plays an important role in constructing artificial intel-ligence(AI)models of industrial control systems(ICSs).Three challenges in this field are learning effective representation from high-dimensio... Feature extraction plays an important role in constructing artificial intel-ligence(AI)models of industrial control systems(ICSs).Three challenges in this field are learning effective representation from high-dimensional features,data heterogeneity,and data noise due to the diversity of data dimensions,formats and noise of sensors,controllers and actuators.Hence,a novel unsupervised learn-ing autoencoder model is proposed for ICS data in this paper.Although traditional methods only capture the linear correlations of ICS features,our deep industrial representation learning model(DIRL)based on a convolutional neural network can mine high-order features,thus solving the problem of high-dimensional and heterogeneous ICS data.In addition,an unsupervised denoising autoencoder is introduced for noisy ICS data in DIRL.Training the denoising autoencoder allows the model to better mitigate the sensor noise problem.In this way,the represen-tative features learned by DIRL could help to evaluate the safety state of ICSs more effectively.We tested our model with absolute and relative accuracy experi-ments on two large-scale ICS datasets.Compared with other popular methods,DIRL showed advantages in four common indicators of AI algorithms:accuracy,precision,recall,and F1-score.This study contributes to the effective analysis of large-scale ICS data,which promotes the stable operation of ICSs. 展开更多
关键词 Industrialcontrolsystem MACHINELEARNING deeplearning autoencoder
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Radiation-Pressure Effects in Cold-Atom Absorption Spectroscopy and Electromagnetically Induced Transparency
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作者 Suying Bai Xiaoxuan Han +3 位作者 Yunchun Jiao Liping Hao jianming zhao Suotang Jia 《Journal of Modern Physics》 2017年第11期1884-1893,共10页
Radiation pressure due to the interaction between a probe light and cold atoms is investigated in a standard cesium magneto-optical trap. The radiation pressure alters the absorption spectroscopy of cold atoms, leadin... Radiation pressure due to the interaction between a probe light and cold atoms is investigated in a standard cesium magneto-optical trap. The radiation pressure alters the absorption spectroscopy of cold atoms, leading to line shapes and linewidths after resonant interaction that are different for positive and negative probe chirps. The difference is attributed to the radiation pressure of the probe laser, due to which atoms become accelerated at the resonance. The effect of the radiation pressure is also seen in electromagnetically induced transparency (EIT) involving an excited Rydberg level. The density matrix equation accounting for the radiation pressure is used to simulate the experiments. The simulations agree well with the measurements both for absorption and EIT spectra. We find that the effect of the radiation pressure is reduced at low probe intensities, and can be neglected when the probe intensity is smaller than Isat/2 . 展开更多
关键词 Radiation Pressure Interaction RYDBERG EIT
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Analysis of Risk Factors of Postoperative Neurological Complications in Patients with Stanford Type A Aortic Dissection Undergoing Sun’s Procedure
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作者 Hui Zhang Ruicheng Zhang +5 位作者 Hua Zhang Feng Li jianming zhao Shen Ma Rujun Zhu Pingfan Wang 《Journal of Clinical and Nursing Research》 2021年第6期93-101,共9页
Objective:This study analyzed the risk factors of neurological complications in patients with Stanford type A aortic dissection after Sun’s procedure in a single-center with the purpose of improving the effects.Metho... Objective:This study analyzed the risk factors of neurological complications in patients with Stanford type A aortic dissection after Sun’s procedure in a single-center with the purpose of improving the effects.Methods:From January 2019 to December 2020,the clinical data of 480 patients with Stanford type A aortic dissection,who were treated by Sun’s procedure in our center were retrospectively analyzed.Univariate and multivariate logistic regression analyses were used to determine the risk factors of postoperative neurological complications.According to whether there were neurological complications after surgery,they were divided into two groups:the group with complications(n=70)and the group without complications(n=410).The clinical data of the two groups were collected and compared.Results:There were 70 cases of patients with postoperative neurological complications in 480 cases.The incidence rates of temporary neurological dysfunction(TND)and permanent neurological dysfunction(PND)was 11.5%(55/480)and 3.1%(15/480),respectively.Univariate analysis showed that the age(≥70 years),stroke history,femoral artery intubation and cardiopulmonary bypass(CPB)time were associated with postoperative PND(p<0.05).Renal dysfunction,emergency surgery,postoperative hypernatremia,postoperative hyperglycemia,postoperative hypoxemia,postoperative low cardiac output syndrome,and assisted time of suction influenced the occurrence of postoperative TND(p<0.05).Multivariate logistic regression analysis showed that age(≥70 years),stroke history,femoral artery intubation and CPB time were independent risk factors for PND.Renal dysfunction,emergency surgery,postoperative hypernatremia,postoperative hyperglycemia,postoperative hypoxemia,postoperative low cardiac output syndrome,and aspiration time were independent risk factors for TND.Compared with the two groups,the hospitalization time and ICU time of the patients in the neurological complications group were significantly prolonged,and the mortality rate was significantly increased(p<0.05).Conclusion:There are many risk factors for neurological complications in patients with Stanford type A aortic dissection after surgery.With the improvement of surgical techniques,optimization of cerebral perfusion,and interventions for risk factors,Sun’s procedure remains the preferred treatment for Stanford type A aortic dissection. 展开更多
关键词 Aortic dissection Neurological complications Sun’s procedure Risk factors
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Injectable and in situ foaming shape-adaptive porous Bio-based polyurethane scaffold used for cartilage regeneration 被引量:2
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作者 Abudureheman Bahatibieke Shuai Wei +9 位作者 Han Feng jianming zhao Mengjiao Ma Junfei Li Yajie Xie Kun Qiao Yanseng Wang Jiang Peng Haoye Meng Yudong Zheng 《Bioactive Materials》 SCIE CSCD 2024年第9期1-13,共13页
Irregular articular cartilage injury is a common type of joint trauma,often resulting from intense impacts and other factors that lead to irregularly shaped wounds,the limited regenerative capacity of cartilage and th... Irregular articular cartilage injury is a common type of joint trauma,often resulting from intense impacts and other factors that lead to irregularly shaped wounds,the limited regenerative capacity of cartilage and the mismatched shape of the scaffods have contributed to unsatisfactory therapeutic outcomes.While injectable materials are a traditional solution to adapt to irregular cartilage defects,they have limitations,and injectable materials often lack the porous microstructures favorable for the rapid proliferation of cartilage cells.In this study,an injectable porous polyurethane scaffold named PU-BDO-Gelatin-Foam(PUBGF)was prepared.After injection into cartilage defects,PUBGF forms in situ at the site of the defect and exhibits a dynamic microstructure during the initial two weeks.This dynamic microstructure endows the scaffold with the ability to retain substances within its interior,thereby enhancing its capacity to promote chondrogenesis.Furthermore,the chondral repair efficacy of PUBGF was validated by directly injecting it into rat articular cartilage injury sites.The injectable PUBGF scaffold demonstrates a superior potential for promoting the repair of cartilage defects when compared to traditional porous polyurethane scaffolds.The substance retention ability of this injectable porous scaffold makes it a promising option for clinical applications. 展开更多
关键词 INJECTABLE In situ forming POLYURETHANE Cartilage repair Tissue engineering
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巴列维王朝的民族政策对伊朗阿塞拜疆人影响探析 被引量:3
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作者 赵建明 《世界民族》 CSSCI 北大核心 2021年第6期43-57,共15页
巴列维王朝是现代伊朗的起点。为抵御外敌和实现富国强兵,国王礼萨·汗开启了伊朗的现代化进程,并将波斯化运动作为现代民族国家构建的手段,系统改造阿塞拜疆等少数民族。但是礼萨·汗推行的波斯化运动造成了伊朗国内波斯民族... 巴列维王朝是现代伊朗的起点。为抵御外敌和实现富国强兵,国王礼萨·汗开启了伊朗的现代化进程,并将波斯化运动作为现代民族国家构建的手段,系统改造阿塞拜疆等少数民族。但是礼萨·汗推行的波斯化运动造成了伊朗国内波斯民族同阿塞拜疆等民族的对立,激发了伊朗的阿塞拜疆民族主义。由于这一时期伊朗仍然积贫积弱,在国家主权甚至内政上并不能完全独立自主。在民族政策上,伊朗国王也不是伊朗现代民族国家建构的唯一决定性因素。随着第二次世界大战的爆发,苏联为攫取利益,选择支持伊朗的阿塞拜疆人对抗中央政府,这让伊朗的阿塞拜疆民族主义得以在苏联保护下兴起,并进而建立阿塞拜疆民主共和国。尽管这一尝试最终因苏联的政策变化归于失败,但它为伊朗的阿塞拜疆民族主义复兴埋下了种子,民族利益受到严重侵害的伊朗阿塞拜疆成了伊斯兰革命的先驱,并最终推翻了巴列维王朝。 展开更多
关键词 阿塞拜疆民族主义 巴列维王朝 波斯化运动 大不里士起义
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光催化氧化交叉偶联制备对称/不对称硫代磺酸酯
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作者 赵健铭 朱佳顺 +2 位作者 沈佳斌 张怡岚 李万梅 《有机化学》 SCIE CAS CSCD 北大核心 2022年第9期2940-2946,共7页
由于其清洁绿色等特点,光催化合成已成为国际化学研究的前沿.报道了一种以硫醇为原料、selectfluor为氧化剂, eosin Y为光催化剂,在蓝光光照下构建S—S(O)_(2)键的方法.该方法具有条件温和,官能团兼容性良好,各种硫醇都能以较好的转化... 由于其清洁绿色等特点,光催化合成已成为国际化学研究的前沿.报道了一种以硫醇为原料、selectfluor为氧化剂, eosin Y为光催化剂,在蓝光光照下构建S—S(O)_(2)键的方法.该方法具有条件温和,官能团兼容性良好,各种硫醇都能以较好的转化率转化成相应的硫代磺酸酯等优点,可为开发条件温和、原子经济性高、普适性强的催化体系以实现含硫有机物高效且可控转化提供了非常有价值的参考. 展开更多
关键词 硫醇 光催化 氧化偶联 硫代磺酸酯
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