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A possible precessing nozzle and the Lense-thirring effect in blazar 3C 454.3

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Research in Astronomy and Astrophysics 2014年第3期14卷 249-274页

作者： Shan-Jie qian S.Britzen A.Witzel t.P.Krichbaum Heng-qian Gan Long Gao National Astronomical Observatories Chinese Academy of Sciences Max-Planck Institt fr Radioastronomie

the kinematics of superluminal components in blazar 3C 454.3 are *** components are included： superluminal knots R1, R2, R3, R4, A, B, C and D（from Britzen et al. 2013） and C4 （from Pauliny-toth 1998）. We find that their kine-matics derived from VLBI observations can be consistently interpreted in terms of ajet precession scenario with a period of about 14.5 yr. We discuss the model fits oftheir trajectory, distance from the core and apparent velocity. We show that the bulkLorentz factor （in the range 4 to 15） derived for these components does not have anydependence on the phase of the precession （or position angle for ejection）. the Lense-thirring effect is assumed to interpret the precession of the jet nozzle. the resultsobtained for blazar 3C 454.3 are only suggestive. they are not unique and have yet tobe tested, but they might be useful for understanding the kinematics of superluminalcomponents in blazars and for disentangling different mechanisms and factors.

关键词： radio continuum: galaxies galaxies: jets galaxies: kinematics galaxies: individual (blazar 3C 454.3)

Guided lithium nucleation and growth on lithiophilic tin-decorated copper substrate

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Journal of Energy Chemistry 2022年第11期31卷 412-419,I0011页

作者： Lang ye Chengyi Zhang yin Zhou BurakÜlgüt yan Zhao Jiangfeng qian Hubei Key Laboratory of Electrochemical Power Sources College of Chemistry and Molecular SciencesWuhan UniversityWuhan 430072HubeiChina Institute of technological Sciences Wuhan UniversityWuhan 430072HubeiChina Faculty of Science Department of ChemistryBilkent UniversityAnkara 06800Turkey

Lithium metal is the ultimate anode choice for high energy rechargeable lithium batteries owing to its ultra-high theoretical capacity,however,Li dendrites and low Coulombic efficiency(CE)caused by disordered Li plating restrict its practical ***,we develop an ultrathin Sn-decorated Cu substrate(Sn@Cu)fabricated by an electroless plating method to induce ordered Li nucleation and growth *** lithiophilic Sn interfacial layer is found to play a critical role to lower the Li nucleation over-potential and promote fast Li-migration kinetics,and the underlying mechanism is revealed using the first principle ***,a dense dendrite-free and Li deposition with large granular morphology is obtained,which significantly improved the CE and cycling performance of Li‖Sn@Cu half cells symmetric *** cells using the Li-Sn@Cu electrode display a much-prolonged life span(>1200 h)with low overpotential(~18 mV)at a high current density of 1 mA cm^(-2).Moreover,full cells paired with commercial LiFePO_(4) cathode(1.8 mAh cm^(-2))deliver enhanced cycling stability(0.5 C,300 cycles)and excellent rate *** work provides a simple and effective way to bring about high efficiency and long lifespan substrates for practical applications.

关键词： Lithium metal anode Lithiophilic tin modification Electroless tin plating Nucleation and growth Li migration kinetics First-principles calculations

A monolithic 3D IGZO-RRAM-SRAM-integrated architecture for robust and efficient compute-in-memory enabling equivalent-ideal device metrics

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Science China(Information Sciences) 2025年

作者： Shengzhe yAN Zhaori CONG Zi WANG Zhuoyu DAI Zeyu GUO Zhihang qian Xufan LI Xu ZHENG Chuanke CHEN Nianduan LU Chunmeng DOU Guanhua yANG Xiaoxin XU Di GENG Jinshan yUE Lingfei WANG Ling LI Ming LIU Institute of Microelectronics of the Chinese Academy of Sciences University of Chinese Academy of Sciences

Abstract Compute-in-memory (CIM) based on various devices such as static random access memory (SRAM) and resistive random access memory (RRAM) and other emerging devices such as indium-gallium-zinc-oxide (IGZO) transistor, magnetoresistive RAM (MRAM), and ferroelectric RAM (FeRAM) has been explored for better performance and energy efficiency on neural networks applications. However, CIM based on a single-type device suffers a variety of non-ideal metrics to reach the simultaneous optimal accuracy, density, and energy efficiency. this work presents equivalent-ideal CIM (Eq-CIM), a monolithic 3D(M3D) IGZO-RRAM-SRAM integrated architecture for robust and efficient compute-in-memory enabling equivalent-ideal device metrics. to overcome the non-ideality (variation, endurance, temperature, etc.) of the single-type devices, system-technology co-optimization (StCO) is performed. this work highlights the non-ideality-aware functionality breakdown for robust high accuracy and simultaneous high density/efficiency, by utilizing 2t0C IGZO for temporal activation storage, RRAM for high-density weight storage, and SRAM for accurate CIM. Device-to-algorithm variation transfer is applied to analyze the system-level accuracy. We benchmark Eq-CIM architecture on CIFAR-10/ImageNet, with 5.06×storage density and 5.05×/2.45×area/energy efficiency compared with single-type-device-based CIM, and high robustness (y loss) from-40℃ to 120℃.

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Food security amid the COVID-19 pandemic in Central Asia:Evidence from rural tajikistan

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Journal of Integrative Agriculture 2024年第8期23卷 2853-2867页

作者： yuhan Zhao Chen qian yumei Zhang Xiande Li Kamiljon t.Akramov Institute of Agricultural Economics and Development Chinese Academy of Agricultural SciencesBeijing 100081China Academy of Global Food Economics and Policy College of Economics and ManagementChina Agricultural UniversityBeijing 100083China International Food Policy Research Institute(IFPRI) WashingtonD.C.20005USA

Food security has been long understudied in the context of Central *** present an analysis examining household-level food demand for tajikistan and assessing the magnitude of its food security changes during the COVID-19 *** on an extensive household survey data set from tajikistan,we estimate the expenditure,income,and price elasticities for nine food categories using the QUAIDS ***,we develop a microsimulation model using the estimated elasticities to assess the dual impact of declining remittance income and rising food prices stemming from the pandemic *** are significant differences in demand elasticities across food groups,with high elasticities observed for nutritious foods,such as meat,fruit,eggs,and milk,in rural ***,our findings show that changes in remittance income and food prices significantly negatively affected food security for rural households during the COVID-19 *** findings have important implications for policymakers concerned about rural livelihoods and food security in remittance-receiving economies during the post-pandemic period.

关键词： international remittances food security COVID-19 tajikistan Central Asia

Intravesical chemotherapy synergize with an immune adjuvant by a thermo-sensitive hydrogel system for bladder cancer

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Bioactive Materials 2024年第1期31卷 315-332页

作者： J.Liu t.y.yang L.Q.Dai K.Shi y.Hao B.y.Chu D.R.Hu Z.W.Bei L.P.yuan M.Pan Z.y.qian Department of Biotherapy Cancer Center and State Key Laboratory of BiotherapyWest China HospitalSichuan UniversityChengdu610041China

Surgical resection remains the prefer option for bladder cancer ***,the effectiveness of surgery is usually limited for the high recurrence rate and poor ***,intravesical chemotherapy synergize with immunotherapy in situ is an attractive way to improve therapeutic ***,a combined strategy based on thermo-sensitive PLEL hydrogel drug delivery system was *** loaded PLEL hydrogel was intravesical instilled to kill tumor cells directly,then PLEL hydrogel incorporated with CpG was injected into both groins subcutaneously to promote immune responses synergize with *** results demonstrated that drug loaded PLEL hydrogel had a sol-gel phase transition behavior in response to physiological temperature and presented sustained drug release,and the PLEL-assisted combination therapy could have better tumor suppression effect and stronger immunostimulating effect in ***,this combined treatment with PLEL hydrogel system has great potential and suggests a clinically-relevant and valuable option for bladder cancer.

关键词： thermo-responsive hydrogel Localized drug delivery Intravesical chemotherapy Immunotherapy Bladder cancer

Positive-instantaneous frequency and approximation

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Frontiers of Mathematics in China 2022年第3期17卷 337-371页

作者： tao qian Macao Center for Mathematical Science Macao University of Science and TechnologyMacaoChina

Positive-instantaneous frequency representation for transient signals has always been a great concern due to its theoretical and practical importance,although the involved concept itself is *** desire and practice of uniqueness of such frequency representation(decomposition)raise the related topics in *** approximately the last two decades there has formulated a signal decomposition and reconstruction method rooted in harmonic and complex analysis giving rise to the desired signal *** method decomposes any signal into a few basic signals that possess positive instantaneous *** theory has profound relations to classical mathematics and can be generalized to signals defined in higher dimensional manifolds with vector and matrix values,and in particular,promotes kernel approximation for multi-variate *** article mainly serves as a *** also gives two important technical proofs of which one for a general convergence result(theorem 3.4),and the other for necessity of multiple kernel(Lemma 3.7).Expositorily,for a given real-valued signal f one can associate it with a Hardy space function F whose real part coincides with *** function F has the form F=f+iHf,where H stands for the Hilbert transformation of the *** develop fast converging expansions of F in orthogonal terms of the form F=∑k=1^(∞)c_(k)B_(k),where B_(k)'s are also Hardy space functions but with the additional properties B_(k)(t)=ρ_(k)(t)e^(iθ_(k)(t)),ρk≥0,θ′_(k)(t)≥0,*** original real-valued function f is accordingly expanded f=∑k=1^(∞)ρ_(k)(t)cosθ_(k)(t)which,besides the properties ofρ_(k)andθ_(k)given above,also satisfies H(ρ_(k)cosθ_(k))(t)ρ_(k)(t)sinρ_(k)(t).Real-valued functions f(t)=ρ(t)cosθ(t)that satisfy the conditionρ≥0,θ′(t)≥0,H(ρcosθ)(t)=ρ(t)sinθ(t)are called *** f is a mono-component,then the phase derivativeθ′(t)is defined to be instantaneous frequency of *** above described positive-instantaneou

关键词： Möbius transform blaschke product mono-component hilbert transform hardy space inner and outer functions adaptive fourier decomposition rational orthogonal system nevanlinna factorization beurling-lax theorem reproducing kernel hilbert space several complex variables Clifford alge-bra pre-orthogonal AFD

Deeply missing my career idol and role model--Professor Perry ***

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Frontiers of Environmental Science & Engineering 2023年第9期17卷 257-258页

作者： yi qian School of Environment Tsinghua UniversityBeijing 100084China

Upon hearing the news of Professor Perry ***’s passing,I felt deeply saddened and heartbroken,and was unable to contain my emotions.I couldn’t help but reminiscing about the cherished moments we shared together and the valuable lessons I learned from him over the years.I first met Professor Perry *** in *** the opportunity of attending a conference in the United States,I visited Professor McKinney at the University of Kansas,the first American expert in my field that I had ever known of.I told him that I was very interested in Professor McCarty’s research on aerobic bio-filters and wanted to learn more.“Let me give Perry a call,”he said immediately,and in less than five minutes,Perry and I became *** turned out that Professor McKinney had been Professor McCarty’s teacher and mentor in the past.I changed my flight immediately and flew to California the next day,where I met Professor McCarty,a world-renowned expert in water pollution control,and visited the aerobic bio-filter he established and their water pollution control *** had inspiring yet amiable conversations,and a friendship that lasted for over 30 years ensued.

关键词： visited career missing

Modeling the measurement precision of Fringe Projection Profilometry

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Light(Science & Applications) 2023年第11期12卷 2480-2497页

作者： Shenzhen Lv qian Kemao School of Computer Science and Engineering Nanyang Technological UniversitySingaporeSingapore

three-dimensional(3D)surface geometry provides elemental information in various sciences and precision *** Projection Profilometry(FPP)is one of the most powerful non-contact(thus non-destructive)and non-interferometric(thus less restrictive)3D measurement techniques,featuring at its high ***,the measurement precision of FPP is currently evaluated experimentally,lacking a complete theoretical model for *** propose the first complete FPP precision model chain including four stage models(camera intensity,fringe intensity,phase and 3D geometry)and two transfer models(from fringe intensity to phase and from phase to 3D geometry).the most significant contributions include the adoption of a non-Gaussian camera noise model,which,for the first time,establishes the connection between camera’s electronics parameters(known in advance from the camera manufacturer)and the phase precision,and the formulation of the phase to geometry transfer,which makes the precision of the measured geometry representable in an explicit and concise *** a result,we not only establish the full precision model of the 3D geometry to characterize the performance of an FPP system that has already been set up,but also explore the expression of the highest possible precision limit to guide the error distribution of an FPP system that is yet to *** theoretical models make FPP a more designable technique to meet the challenges from various measurement demands concerning different object sizes from macro to micro and requiring different measurement precisions from a few millimeters to a few micrometers.

关键词： sizes concerning formulation

Asymptotic Estimates on the time Derivative of Φ-entropy on Riemannian Manifolds

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Acta Mathematica Sinica,English Series 2014年第4期30卷 609-618页

作者： Bin qian Department of Mathematics Changshu Institute of Technology

In this note, we obtain an asymptotic estimate for the time derivative of the O-entropy in terms of the lower bound of the Bakry-Emery F2 curvature. In the cases of hyperbolic space and the Heisenberg group （more generally, the nilpotent Lie group of rank two）, we show that the time derivative of the O-entropy is non-increasing and concave in time t, also we get a sharp asymptotic bound for the time derivative of the entropy in these cases.

关键词： Ф-entropy curvature heat kernel hyperbolic space