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Realizing quantum imaginary time evolution in experiment

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Science China(Physics,Mechanics & Astronomy) 2024年第4期67卷 167-168页

作者： xiao yuan Center on Frontiers of Computing Studies Peking UniversityBeijing 100871China School of Computer Science Peking UniversityBeijing 100871China

NISQ,or Noisy Intermediate-Scale Quantum computing,represents a pivotal and the state-of-the-art quantum technology[1].Characterized by intermediate-scale quantum devices that are beyond classical computational capabilities yet fall short of the error-correction thresholds required for fault-tolerant quantum computing,NISQ devices exhibit both promise and *** devices hold immense potential in solving certain computational problems that surpass classical capabilities,with wide applications in optimization,machine learning,and quantum chemistry.

关键词： quantum imaginary correction

The steroid-induced microRNA let-7 regulates developmental growth by targeting cdc7 in the Drosophila body

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Insect Science 2021年第6期28卷 1621-1632页

作者： Dan-Yan huang xiao-Ling Xia Run huang Sheng Li Dong-Wei yuan Su-Ning Liu Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology Institute of Insect Science and Technology&School of Life SciencesSouth China Normal UniversityGuangzhou510631China

In insects,20-hydroxyecdysone(20E)limits systemic growth by triggering developmental *** studies have shown that 20E-induced let-7 exhibits crosstalk with the cell ***,we examined the underlying molecular mechanisms and physiological functions of 20E-induced let-7 in the fat body,an organ for energy storage and nutrient mobilization which plays a critical role in the larval ***,the overexpression of let-7 decreased the body size and led to the reduction of both nucleolus and cell sizes in the larval fat *** contrast,the overexpression of let-7-Sponge increased the nucleolus and cell ***,we found that cdc7,encoding a conserved protein kinase that controls the endocycle,is a target of ***,the mutation of cdc7 in the fat body resulted in growth ***,our findings revealed a novel role of let-7 in the control of endoreduplication-related growth during larval-prepupal transition in Drosophila.

关键词： cdc7 Drosophila fat body growth let-7

Wear mechanism of heavy load friction contact pairs in tracked vehicle by combined ferrography and surface analysis

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中国有色金属学会会刊:英文版 2004年第z1期14卷 348-353页

作者： LI Li ZHU You-li huang yuan-lin XU Bin-shi LI xiao-yan National Key Laboratory for Remanufacturing Academy of Armored Force EngineeringBeijing 100072 China College of Materials Science and Engineering Beijng University of TechnologyBeijing 100022 China

Ferrography is deemed as one of the most effective methods for wear particle analysis and failure diagnosis. By analyzing the configuration, content and composition of wear particles in the lubricanting grease and the surface state of the worn surface with combined ferrography and surface analysis techniques, the wear mechanism of the ball groove of the master clutch's release device of a heavy load tracked vehicle was determined. Results show that the controlling wear mechanism is combined of abrasion, adhesion, contact fatigue and corrosion wear, which demonstrates the effectiveness of using combined ferrography and worn surface analysis for the study of wear mechanism of contact surface with friction.

关键词： ferrography surface analysis wear failure analysis lubricanting grease

Hugoniot equation of state of olivine and its geodynamic implications

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Science China Earth Sciences 2016年第3期59卷 619-625页

作者： huang xiao Ge yuan Xian Hao CHEN Zu An LIU Fu Sheng BAI Wu Ming Key Laboratory of Earth and Planetary Physics Institute of Geology and Geophysics Chinese Academy of Sciences Institute of High Temperature and High Pressure Physics Key Laboratory of Advanced Technologies of Materials Ministry of Education of China Southwest Jiaotong University

Large olivine samples were hot-pressed synthesized for shock wave experiments. The shock wave experiments were carried out at pressure range between 11 and 42 GPa. Shock data on olivine sample yielded a linear relationship between shock wave velocity D and particle velocity u described by D=3.56(?0.13)+2.57(?0.12)u. The shock temperature is determined by an energy relationship which is approximately 790°C at pressure 28 GPa. Due to low temperature and short experimental duration, we suggest that no phase change occurred in our sample below 30 GPa and olivine persisted well beyond its equilibrium boundary in metastable phase. The densities of metastable olivine are in agreement with the results of static compression. At the depth shallower than 410 km, the densities of metastable olivine are higher than those of the PREM model, facilitating cold slab to sink into the mantle transition zone. However, in entire mantle transition zone, the shock densities are lower than those of the PREM model, hampering cold slab to flow across the "660 km" phase boundary.

关键词： Hugonite density Shock temperature Olivine Mantle transition zone

Control Model of Multifunctional Hot Metal Ladles

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Journal of Iron and Steel Research International 2016年第12期23卷 1262-1267页

作者： Bang-fu huang Nai-yuan TIAN Zhi wei MA Zhe SHI xiao-lei ZHOU Faculty of Metallurgical and Energy Engineering Kunming University of Science and TechnologyKunming 650093YunnanChina Clean Metallurgy Key Laboratory of Complex Iron Resources Kunming 650093YunnanChina School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

For further research on the control model of muhifunctional hot metal ladles between the ironmaking and steelmaking interface, the hot metal ladies of K steel plant were taken as the object to analyze the operation process. The factors of blast furnace supply and basic oxygen furnace demand were proposed. According to the principle of supply and demand balance, the control model of hot metal was researched under the following factor conditions： equal to, greater than, and less than 1, respectively. The distribution model of the blast furnace, sleelmaking works, and online buffering was proposed. When the supply and demand factor is equal to ） , the turnover number of hot metal ladles equals 16 and the turnover cycle of hot metal ladles equals 512 min. When the factor is greater than 1, the total number of hot metal ladles is equal to the normal turnover number plus the turnover number of the cast iron machine. When the factor is less than 1, the total number of hot metal ladles is equal tO the normal turnover number plus the accumulating number. Satisfactory effects were obtained by applying the control model in produc tion. The numbers of turnover ladles and accumulating ladles were reduced.

关键词： ironmaking steelmaking interface muhifunctional hot metal ladle control model blast furnace basic oxygen furnace

Novel functional fiber loaded with carbon dots for the deep removal of Cr(Ⅵ) by adsorption and photocatalytic reduction

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Journal of Environmental Sciences 2019年第9期31卷 195-204页

作者： Junfeng xiao yuanpeng Cheng Caixia Guo Xiangting Liu Bing Zhang Siguo yuan Jiajia huang School of Chemical Engineering and Energy Zhengzhou University

A novel functional fiber(PAN-CDs) loaded with carbon dots(CDs) with excellent photoreduction and adsorption properties for Cr(VI) was prepared via an amidization reaction between the CDs’ carboxyl groups and amine groups on polyacrylonitrile(PAN)-based ion exchange fibers, which could completely preserve the fluorescence properties of the CDs. The photoluminescence(PL), photocatalysis and adsorption properties of PAN-CDs were characterized and analyzed. The PAN-CDs possess high adsorption capacity(297.6 mg/g) and excellent kinetic behavior(attaining adsorption equilibrium in 30 min)for Cr(VI) adsorption. Furthermore, the residual Cr(VI)(approximately 3 mg/L) after adsorption could be removed completely by subsequent photoreduction by the *** Cr-saturated PAN-CDs could be easily separated by filtering and regenerated, with no observable decay of removal efficiency after five regeneration cycles. In addition, due to the PL quenching action of Cr(VI), the PAN-CDs can also be used as sensor for quantitative detection of trace Cr(VI) in aqueous solution.

关键词： Fluorescence Cr(VI) Adsorption Photoreduction Carbon dots

Copper/cuprous sulfide electrode: preparation and performance

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Science China Chemistry 2015年第6期58卷 1039-1043页

作者： Lina xiao Ding yuan Pei Li Li huang Bing-Wei Mao Dongping Zhan State Key Laboratory for Physical Chemistry of Solid Surfaces Department of Chemistry College of Chemistry and Chemical Engineering Xiamen University

Cuprous sulfide （Cu2S） is a direct band-gap p-type semiconductor with excellent ionic/electronic hybrid conductivity. Alt- hough Cu/Cu2S/sulfide or polysulfide system is adopted as counter electrode of quantum-dots-sensitized solar cells （QDSSC）, the electrode process is seldom reported. Here, the electrochemical growth of Cu2S film on a copper （Cu） surface, the redox behaviors of sulfide and polysulfide, and the all-in-solid charge-transfer properties of Cu2S film are investigated. It is clarified that the copper electrode simultaneously undergoes an activated process, a membrane growth process, and a redox phase transformation process. The solid charge-transfer capability of CuzS is quantified with a high exchange-current density of 2.27 A/cm2, which elucidates that the Cu/CuzS electrode is a qualified material for counter electrodes of QDSSC. These results aid understanding of the physicochemical mechanism of QDSSC with a polysulfide electrolyte and Cu/Cu2S counter electrode.

关键词： quantum dots sensitized solar cells counter electrode cuprous sulfide film growth

Desulfurization of Petroleum Coke by Calcination in Ammonia Atmosphere below 1000℃

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China Petroleum Processing & Petrochemical Technology 2016年第4期18卷 41-50页

作者： Zhong Qifan xiao Jin huang Jindi yuan Jie Yu Bailie school of metallurgy and environment central south universityChangsha410083 national engineering laboratory of efficient utilization of refractory nonferrous metal resources central south universityChangsha410083

The desulfurization efficiency and mechanism of the calcination of petroleum coke in ammonia atmosphere at lower than 1000 ℃ were investigated through a series of conditional experiments and comparison with other gases such as H_2. The topics of efficiency and reaction mechanism are usually discussed through investigation by means of the Fourier transform infrared spectroscopy(FT-IR), the Brunauer-Emmett-Teller(BET) technique, and the thermogravimetry coupled with the mass spectrometry(TG-MS). Results showed that in addition to H_2, ammonia not only could retain a high desulfurization rate but could also reduce coke loss during the desulfurization process of petroleum coke. The best desulfurization conditions covered a petroleum coke particle size of less than 0.1 mm, a calcination temperature of 800 ℃ in ammonia atmosphere with a flow rate of 10 L/h, and a heating duration of more than 120 min. Ammonia decomposition, H_2 generation, decline in the activation energy of the carbon–sulfur bonds, and petroleum coke with a largest specific surface area at 800 ℃ are the key goals of desulfurization studied thereby. As proved by TG-MS analysis, given a large quantity of H_2, ammonia can be decomposed at the same temperature to completely come into contact with the sulfur species in petroleum coke to generate H_2S.

关键词： desulfurization petroleum coke ammonia calcination TG-MS

Rice MtN3/saliva/SWEET gene family: Evolution,expression profiling, and sugar transport

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Journal of Integrative Plant Biology 2014年第6期56卷 559-570页

作者： Meng yuan Junwei Zhao Renyan huang Xianghua Li Jinghua xiao Shiping Wang National Key Laboratory of Crop Genetic Improvement National Center of Plant Gene Research (Wuhan) Huazhong Agricultural University

The rice MtN3/saliva/SWEET gene family consists of 21 paralogs. However, their functions in physiological processes are largely unknown, although at least three of the 21 paralogs are used by pathogenic bacteria to infect rice. Here, we report the evolutionary features, transcriptional characteristics, and putative functions in sugar transport of this gene family. The wild rice accessions in this study included those with AA, BB, CC, BBCC, CCDD, EE, and GG genomes, which appeared approximately 0.58-14.6 million years ago. The structures, chromosomal locations, phylogenetic relationships, and homologous distribution among the accessions suggest that the number of rice MtN3/saliva/SWEET paralogs gradual y increased as the Oryza genus evolved, and one third of the paralogs may have originated recently. These paralogs are differentially expressed in vegetative and reproductive tissues, in the leaf senescence process, and in signaling dependent on gibberel ic acid, cytokinin, or 1-naphthalene acetic acid （an analog of auxin）, suggesting that they may be associated with multiple physiological processes. Four paralogs could transport galactose in yeast, which suggests that they may have a similar function in rice. These results will help to elucidate their roles and biochemical functions in rice development, adaptation to environment, host-pathogen interaction, and so forth.

关键词： Evolution MtN3/saliva domain Oryza sotivo transporter