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Chinese Physics C 2024年第8期48卷 198-212页

作者： zhi-chao wang Xian Gao School of Physics and Astronomy Sun Yat-sen UniversityZhuhai 519082China

We investigate a class of gravity theories respecting only spatial covariance,termed spatially covariant gravity,in the presence of an auxiliary scalar *** examine the conditions on the Lagrangian required to eliminate scalar degrees of freedom,allowing only two tensorial degrees of freedom to *** of strict constraint analysis,in this paper,we employ the perturbation method and focus on the necessary conditions to evade the scalar mode at the linear order in perturbations around a cosmological *** with a general action and solving the auxiliary perturbation variables in terms of a would-be dynamical scalar mode,we derive the condition to remove its kinetic term,thus ensuring that no scalar mode *** an application of the general condition,we study a polynomial-type Lagrangian as a concrete example,in which all monomials are spatially covariant scalars containing two *** find that the auxiliary scalar field is essential,and new terms in the Lagrangian are *** analysis provides insights into constructing gravity theories with two degrees of freedom in the extended framework of spatially covariant gravity.

关键词： modified gravity cosmological perturbation theory gravitational theory

Deciphering a Million-Plus RSA Integer with Ultralow Local Field Coefficient h and Coupling Coefficient J of the Ising Model by D-Wave 2000Q

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Tsinghua Science and Technology 2024年第3期29卷 874-882页

作者： chao wang Qiaoyun Hu Haonan Yao Sumin wang zhi Pei Joint International Research Laboratory of Specialty Fiber Optics and Advanced Communication Shanghai UniversityShanghai 200444China

This work is the first to determine that a real quantum computer(including generalized and specialized)can decipher million-scale RSA relying solely on quantum algorithms,showing the real attack potential of D-Wave *** influence of different column widths on RSA factorization results is studied on the basis of a multiplication table,and the optimal column method is determined by traversal *** traversal experiment of integer factorization within 10000 shows that the local field and coupling coefficients are 75%–93%lower than the research of Shanghai University in 2020 and more than 85%lower than that of Purdue University in *** low Ising model parameters are crucial to reducing the hardware requirements,prompting factoring 1245407 on the D-Wave 2000Q real machine.D-Wave advantage already has more than 5000 qubits and will be expanded to 7000 qubits during 2023–2024,with remarkable improvements in decoherence and *** machine is expected to promote the solution of large-scale combinatorial optimization *** of the contributions of this paper is the discussion of the long-term impact of D-Wave on the development of post-quantum cryptography standards.

关键词： quantum annealing RSA D-Wave 2000Q post-quantum cryptography

Primary squamous cell carcinoma with sarcomatoid differentiation of the kidney associated with ureteral stone obstruction: A case report

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World Journal of Clinical Cases 2022年第32期10卷 11942-11948页

作者： Xue-Hua Liu Qian-Ming Zou Jia-Dong Cao zhi-chao wang Department of Urology Surgery Fangcun Hospital of Guangdong Provincial Hospital of traditional Chinese MedicineGuangzhou 510120Guangdong ProvinceChina

BACKGROUND Primary squamous cell carcinoma(SCC)with sarcomatoid differentiation of the kidney was rarely *** disease is usually related to renal stones,and due to a lack of symptoms and radiological features,patients usually attend the hospital with late stage *** SUMMARY A 54-years-old female presented with left flank pain and an abdominal mass for 6 *** studies revealed that the left kidney was enlarged and massive hydronephrosis was present.A stone was seen in the ureteropelvic *** patient subsequently underwent left radical nephrectomy,and histopathological examination of the mass revealed a poorly differentiated renal SCC with sarcomatoid *** primary surgery,the patient received four cycles of *** months later,the patient developed adrenal,lymph,and uterine appendage *** SCC of the kidney has a poor prognosis,and should be considered in patients with a renal mass,long-standing urinary calculi and massive hydronephrosis.

关键词： Squamous cell carcinoma Sarcomatoid differentiation Kidney Ureteral stone Case report

Effect of preparation methods on Pt/alumina catalysts for the hydrogen iodide catalytic decomposition

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Chinese Chemical Letters 2009年第1期20卷 102-105页

作者： zhi chao wang Lai Jun wang Ping Zhang Song Zhe Chen Jing Ming Xu Jing Chen Laboratory 201 Institute of Nuclear and New Energy Technology Tsinghua University Beijing 102201 China

Three kinds of Pt/alumina catalysts were prepared by impregnation-hydrogen reduction, impregnation-hydrazine reduction and electroless plating methods. Their differences in the structures, specific areas and particle sizes were characterized by XRD, BET and TEM, respectively. Furthermore, their catalytic activities for the hydrogen iodide （HI） decomposition were evaluated in a fixed bed reactor. The results show that the catalyst 5%Pt/Al2O3 prepared by the electroless plating has the optimum catalytic properties for HI decomposition owing to the high dispersion of the platinum nano-particles （〈5 nm） on the alumina supports.

关键词： Hydrogen iodide Catalytic decomposition Pt/At2O3 Preparation methods

Switching,explosion,and chaos of multi-wavelength soliton states in ultrafast fiber lasers

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 82-90页

作者： zhi-Zeng Si Yue-Yue wang chao-Qing Dai College of Optical Mechanical and Electrical EngineeringZhejiang A&F UniversityLin’an 311300China

Because of the complexity and difficulty of realizing a multi-wavelength soliton state,reports on its internal dynamic characteristics are *** this study,the switching and periodic soliton explosion processes of the multi-wavelength soliton state in a negative dispersion passively mode-locked fiber laser are *** generation of the multi-wavelength soliton state undergoes the process of noise,oscillation,and stable mode-locking,and the splitting and annihilation of solitons with different group velocities directly impact the generation and disappearance of three *** and negative dispersion lead to different group velocities of *** presence and displacement of solitons with different group velocities cause soliton collisions,which lead to soliton explosions.A soliton experiences relative phase oscillation,chaos,and oscillation,as well as convergence and separation before and after an *** an increase in parameters related to pump power,single-soliton oscillation,multi-wavelength solitons,and chaos are found in experiments and simulations,proving the relevance and reliability between simulation and experimental *** work promotes the dynamical study of multi-soliton collisions in nonlinear science and the development of chaos theory in multi-comb lasers.

关键词： multi-wavelength fiber laser soliton explosion chaos state switching real-time dynamics

Research progress on micro-force measurement of a hydrate particle system

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Petroleum Science 2024年第4期21卷 2169-2183页

作者： Qiang Luo Wei Li zhi-Hui Liu Feng wang zhi-chao Liu Fu-Long Ning Faculty of Engineering China University of Geosciences (Wuhan) Suzhou Laboratory

It remains a great challenge to understand the hydrates involved in phenomena in practical oil and gas systems. The adhesion forces between hydrate particles, between hydrate particles and pipe walls, and between hydrate particles and reservoir particles are essential factors that control the behaviors of clathrate hydrates in different applications. In this review, we summarize the typical micro-force measurement apparatus and methods utilized to study hydrate particle systems. In addition, the adhesion test results, the related understandings, and the applied numerical calculation models are systematically discussed.

关键词： Clathrate hydrates Hydrate particle Micro-force measurements Adhesion Interactions

Quantifying the Tension between Cosmological Models and JWST Red Candidate Massive Galaxies

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Research in Astronomy and Astrophysics 2024年第4期24卷 1-6页

作者： Jun-chao wang zhi-Qi Huang Lu Huang Jianqi Liu School of Physics and Astronomy Sun Yat-sen UniversityZhuhai 519082China CSST Science Center for the Guangdong-Hong Kong-Macao Greater Bay Area Zhuhai519082China CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China

We develop a Python tool to estimate the tail distribution of the number of dark matter halos beyond a mass threshold and in a given volume in a *** code is based on the extended Press-Schechter model and is computationally efficient,typically taking a few seconds on a personal laptop for a given set of cosmological *** high efficiency of the code allows a quick estimation of the tension between cosmological models and the red candidate massive galaxies released by the James Webb Space Telescope,as well as scanning the theory space with the Markov Chain Monte Carlo *** an example application,we use the tool to study the cosmological implication of the candidate galaxies presented in Labbéet *** standard Λcold dark matter(ΛCDM)model is well consistent with the data if the star formation efficiency can reach~0.3 at high *** a low star formation efficiency ε~0.1,theΛCDM model is disfavored at~2σ-3σconfidence level.

关键词： (cosmology:)cosmological parameters Galaxy:abundances Galaxy:formation

An Immune-Inspired Approach with Interval Allocation in Solving Multimodal Multi-Objective Optimization Problems with Local Pareto Sets

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Computers, Materials & Continua 2024年第6期79卷 4237-4257页

作者： Weiwei Zhang Jiaqiang Li chao wang Meng Li zhi Rao College of Computer Science and Technology Zhengzhou University of Light IndustryZhengzhou450001China Technology Research and Development Center Jilin Tobacco Industry Company LimitedChangchun130031China College of Tobacco Science and Engineering Zhengzhou University of Light IndustryZhengzhou450001China Raw Material Department Hongyun Honghe Tobacco(Group)CompanyKunming650202China

In practical engineering,multi-objective optimization often encounters situations where multiple Pareto sets(PS)in the decision space correspond to the same Pareto front(PF)in the objective space,known as Multi-Modal Multi-Objective Optimization Problems(MMOP).Locating multiple equivalent global PSs poses a significant challenge in real-world applications,especially considering the existence of local *** identifying and locating both global and local PSs is a major *** tackle this issue,we introduce an immune-inspired reproduction strategy designed to produce more offspring in less crowded,promising regions and regulate the number of offspring in areas that have been thoroughly *** approach achieves a balanced trade-off between exploration and ***,we present an interval allocation strategy that adaptively assigns fitness levels to each *** strategy ensures a broader survival margin for solutions in their initial stages and progressively amplifies the differences in individual fitness values as the population matures,thus fostering better population ***,we incorporate a multi-population mechanism that precisely manages each subpopulation through the interval allocation strategy,ensuring the preservation of both global and local *** results on 21 test problems,encompassing both global and local PSs,are compared with eight state-of-the-art multimodal multi-objective optimization *** results demonstrate the effectiveness of our proposed algorithm in simultaneously identifying global Pareto sets and locally high-quality PSs.

关键词： Multimodal multi-objective optimization problem local PSs immune-inspired reproduction

Self-reported Taste and Smell Disorders in Patients with COVID-19:Distinct Features in China

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Current Medical Science 2021年第1期41卷 14-23页

作者： Jia SONG Yi-ke DENG Hai wang zhi-chao wang Bo LIAO Jin MA chao HE Li PAN Yang LIU Isam Alobid De-yun wang Ming ZENG Joaquim Mullol Zheng LIU Department of Otolaryngology-Head and Neck Surgery Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Rhinology Unit and Smell Clinic ENT DepartmentHospital ClinicIDIBAPSUniversitat de BarcelonaCIBERESBarcelona 08036Spain Department of Otolaryngology Yong Loo Lin School of MedicineNational University of Singapore 699010Singapore

Last December 2019,a cluster of viral pneumonia cases identified as coronavirus disease 2019(COVID-19)was reported in Wuhan,*** aimed to explore the frequencies of nasal symptoms in patients with COVID-19,including loss of smell and taste,as well as their presentation as the first symptom of the disease and their association with the severity of *** this retrospective study,1206 laboratory-confirmed COVID-19 patients were included and followed up by telephone one month after discharged from Tongji Hospital,*** data,laboratory values,comorbidities,symptoms,and numerical rating scale scores(0–10)of nasal symptoms were extracted from the hospital medical records,and confirmed or reevaluated by the telephone *** patients(n=1172)completing follow-up,199(17%)subjects had severe COVID-19 and 342(29.2%)reported nasal symptoms.20.6%COVID-19 patients had loss of taste(median score=6),while 11.4%had loss of smell(median score=5).Loss of taste scores,but not loss of smell scores,were significantly increased in severe *** COVID-19 ***(IL)-6 and lactose dehydrogenase(LDH)serum levels were positively correlated with loss of taste *** 80%of COVID-19 patients recovered from smell and taste dysfunction in 2 *** this cohort,only 1 out of 10 hospital admitted patients had loss of smell while 1 out of 5 reported loss of taste which was associated to severity of *** patients recovered smell and taste dysfunctions in 2 weeks.

关键词： taste smell coronavirus disease 2019 severe acute respiratory syndrome coronavirus 2

Synergistic effect of Zr and Mo on precipitation and high-temperature properties of Al-Si-Cu-Mg alloys

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China Foundry 2024年第1期21卷 71-81页

作者： chao Gao Bing-rong Zhang Yin-ming Li zhi-ming wang Xiang-bin Meng Faculty of Mechanical Engineering Qilu University of Technology(Shandong Academy of Sciences)Jinan 250353China Hebei Ounai Machinery Mould Co.Ltd. Xingtai 054500HebeiChina

This study focuses on finding a solution to the sharp decline in mechanical properties of Al-Si-Cu-Mg alloys due to rapid coarsening of traditional intermediate phases at high temperature.A new type of modified al oy,to be used in automobile engines at high temperatures,was prepared by adding Zr and Mo into Al-Si-Cu-Mg *** synergistic effects of Zr and Mo on the microstructure evolution and high-temperature mechanical properties were *** show that the addition of Zr and Mo generates a series of intermetallic phases dispersed in the *** can improve the strength of the alloy by hindering dislocation movement and crack *** addition,some nano-strengthened phases show coherent interfaces with the matrix and improve grain *** addition of Mo greatly improves the heat resistance of the *** extremely low diffusivity of Mo enables it to improve the thermal stability of the intermetallic phases,inhibit precipitation during aging,reduce the size of the precipitates,and improve the heat resistance of the alloy.

关键词： Al-Si-Cu-Mg alloy high-temperature properties Zr-Mo-rich intermetallics nano-strengthening phases