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基于2,2-联吡啶3,3-二甲酸和邻菲咯啉的稀土配合物的合成、结构和性质

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福建师范大学学报（自然科学版） 2013年第3期29卷 1-4页

作者：钟琴娣辛林福建师范大学数学与计算机科学学院福建福州350007

以LnCl3、H2bpdc（2,2-联吡啶3,3-二甲酸）和phen（邻菲咯啉）为原料,在水热条件下合成了一系列稀土配合物[Ln（bpdc）1.5（phen）（H2O）]xH2O（Ln=La（1）,Sm（3）和Dy（5）,x=0;Ln=Pr（2）和Gd（4）,x=0.15）,并通过单晶X-射线衍射... 详细信息

以LnCl3、H2bpdc（2,2-联吡啶3,3-二甲酸）和phen（邻菲咯啉）为原料,在水热条件下合成了一系列稀土配合物[Ln（bpdc）1.5（phen）（H2O）]xH2O（Ln=La（1）,Sm（3）和Dy（5）,x=0;Ln=Pr（2）和Gd（4）,x=0.15）,并通过单晶X-射线衍射分析法测定了它们的晶体结构.此外,对配合物3和5的荧光性质和配合物2和4的磁性质进行了研究.结果表明,配合物3和5在室温下均表现出相应稀土离子的特征荧光发射,在配合物2和4的稀土离子间均存在反铁磁相互作用.

关键词：稀土(Ⅲ) 配合物 2,2-联吡啶3,3-二甲酸荧光性质磁性

THE FRAGMENTS OF COMET HYAKUTAKE (C/1996 B2)

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紫金山天文台台刊 1998年第2期 55-58页

作者： Chen Dao-han Zhao Ai-di Wu qin-di Song Yi Fan Yi-xin(Purple Mountain Observatory, Academia Sinica , Nanjing 210008, China )Sun Shou-sheng Zhang Yan Sun Li-nan :(qingdao Station of Purple Mountain Observatory, qingdao 266003, China)

Several fragments of Comet Hyakutake were observed in March and April of 1996. This leads to the impression that the splitting of Comet Hyakutake on a small scale occurred frequently. Data analysis points to a rotatio... 详细信息

关键词： Comet Hyakutake fragment rotation period.

C-CORE:Clustering by Code Representation to Prioritize Test Cases in Compiler Testing

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Computer Modeling in Engineering & Sciences 2024年第5期139卷 2069-2093页

作者： Wei Zhou Xincong Jiang Chuan qin School of Electronic Information and Electrical Engineering Shanghai Jiao Tong UniversityShanghai200240China Hikvision Research Institute Hangzhou Hikvision Digital Technology Co.Ltd.Hangzhou310051China

Edge devices,due to their limited computational and storage resources,often require the use of compilers for program ***,ensuring the security and reliability of these compilers is of paramount importance in the emerging field of edge *** widely used testing method for this purpose is fuzz testing,which detects bugs by inputting random test cases into the target ***,this process consumes significant time and *** improve the efficiency of compiler fuzz testing,it is common practice to utilize test case prioritization *** researchers use machine learning to predict the code coverage of test cases,aiming to maximize the test capability for the target compiler by increasing the overall predicted coverage of the test ***,these methods can only forecast the code coverage of the compiler at a specific optimization level,potentially missing many optimization-related *** this paper,we introduce C-CORE(short for Clustering by Code Representation),the first framework to prioritize test cases according to their code representations,which are derived directly from the source *** approach avoids being limited to specific compiler states and extends to a broader range of compiler ***,we first train a scaled pre-trained programming language model to capture as many common features as possible from the test cases generated by a *** this pre-trained model,we then train two downstream models:one for predicting the likelihood of triggering a bug and another for identifying code representations associated with ***,we cluster the test cases according to their code representations and select the highest-scoring test case from each cluster as the high-quality test *** reduction in redundant testing cases leads to time *** evaluation results reveal that code representations are better at distinguishing test capabilities,and C-CORE significantly enhanc

关键词： Compiler testing test case prioritization code representation

Random Forest-Based Fatigue Reliability-Based Design Optimization for Aeroengine Structures

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 665-684页

作者： Xue-qin Li Lu-Kai Song School of Energy and Power Engineering Beihang UniversityBeijing100191China Department of Mechanical Engineering The Hong Kong Polytechnic UniversityKowloonHong Kong999077China Research Institute of Aero-Engine Beihang UniversityBeijing100191China

Fatigue reliability-based design optimization of aeroengine structures involves multiple repeated calculations of reliability degree and large-scale calls of implicit high-nonlinearity limit state function,leading to the traditional direct Monte Claro and surrogate methods prone to unacceptable computing efficiency and *** this case,by fusing the random subspace strategy and weight allocation technology into bagging ensemble theory,a random forest(RF)model is presented to enhance the computing efficiency of reliability degree;moreover,by embedding the RF model into multilevel optimization model,an efficient RF-assisted fatigue reliability-based design optimization framework is *** the low-cycle fatigue reliability-based design optimization of aeroengine turbine disc as a case,the effectiveness of the presented framework is *** reliabilitybased design optimization results exhibit that the proposed framework holds high computing accuracy and computing *** current efforts shed a light on the theory/method development of reliability-based design optimization of complex engineering structures.

关键词： Random forest reliability-based design optimization ensemble learning machine learning

L_(1)-Smooth SVM with distributed Adaptive Proximal Stochastic Gradient Descent with Momentum for Fast Brain Tumor Detection

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Computers, Materials & Continua 2024年第5期79卷 1975-1994页

作者： Chuandong qin Yu Cao Liqun Meng School of Mathematics and Information Science North Minzu UniversityYinchuan750021China Ningxia Key Laboratory of Intelligent Information and Big Data Processing Yinchuan750021China

Brain tumors come in various types,each with distinct characteristics and treatment approaches,making manual detection a time-consuming and potentially ambiguous *** tumor detection is a valuable tool for gaining a deeper understanding of tumors and improving treatment *** learning models have become key players in automating brain tumor *** descent methods are the mainstream algorithms for solving machine learning *** this paper,we propose a novel distributed proximal stochastic gradient descent approach to solve the L_(1)-Smooth Support Vector Machine(SVM)classifier for brain tumor ***,the smooth hinge loss is introduced to be used as the loss function of *** avoids the issue of nondifferentiability at the zero point encountered by the traditional hinge loss function during gradient descent ***,the L_(1) regularization method is employed to sparsify features and enhance the robustness of the ***,adaptive proximal stochastic gradient descent(PGD)with momentum,and distributed adaptive PGDwithmomentum(DPGD)are proposed and applied to the L_(1)-Smooth *** computing is crucial in large-scale data analysis,with its value manifested in extending algorithms to distributed clusters,thus enabling more efficient processing ofmassive amounts of *** DPGD algorithm leverages Spark,enabling full utilization of the computer’s multi-core *** to its sparsity induced by L_(1) regularization on parameters,it exhibits significantly accelerated convergence *** the perspective of loss reduction,DPGD converges faster than *** experimental results show that adaptive PGD withmomentumand its variants have achieved cutting-edge accuracy and efficiency in brain tumor ***-trained models,both the PGD andDPGD outperform other models,boasting an accuracy of 95.21%.

关键词： Support vector machine proximal stochastic gradient descent brain tumor detection distributed computing

The Monsky Matrices and Non-congruent Numbers

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Algebra Colloquium 2024年第2期31卷 239-262页

作者： Guilin Li Hourong qin Fei Xu Department of Mathematics Nanjing UniversityNanjing 210093China 不详

We give some sufficient conditions for non-congruent numbers in terms of the Monsky *** known criteria for non-congruent numbers can be viewed as special cases of our results.

关键词： congruent elliptic curve Selmer group Monsky matrix non-congruent number

重组慢病毒表达载体介导HIV-1 Vpr蛋白调控KSHV潜伏感染的初探

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中华微生物学和免疫学杂志 2010年第12期30卷 1097-1104页

作者：贾雪梅王平秦娣卢春南京医科大学微生物学与免疫学系 210029

目的利用慢病毒载体系统包装含人类免疫缺陷病毒1型（HIV-1）病毒蛋白R（Vpr）的重组慢病毒,使之感染原发性渗出性淋巴瘤（PEL）细胞BCBL-1,并检测Vpr蛋白对细胞中卡波济肉瘤相关疱疹病毒（KSHV）潜伏感染与裂解性复制的影响.方法从... 详细信息

目的利用慢病毒载体系统包装含人类免疫缺陷病毒1型（HIV-1）病毒蛋白R（Vpr）的重组慢病毒,使之感染原发性渗出性淋巴瘤（PEL）细胞BCBL-1,并检测Vpr蛋白对细胞中卡波济肉瘤相关疱疹病毒（KSHV）潜伏感染与裂解性复制的影响.方法从实验室先前构建的重组真核表达质粒pCI-neo-Vpr中扩增出Vpr基因,插入到pHAGE-CMV-MCS-IzsGreen载体中构建成重组慢病毒质粒pHAGE-Vpr,利用脂质体将其与包装质粒psPAX2及包膜质粒pMD2.G共转染293T细胞,荧光显微镜观察293T细胞中绿色荧光蛋白（GFP）的表达,293T细胞培养上清经0.45 μm滤器过滤后即获得重组病毒悬液.慢病毒系列稀释后感染293T细胞,荧光计数法测定病毒滴度,逆转录PCR（RT-PCR）检测Vpr基因在293T细胞中的转录.以感染复数（MOI）为1的病毒量感染靶细胞BCBL-1,荧光显微镜观察靶细胞中GFP的表达,并利用RT-PCR和和免疫印迹（Western blot）技术分别检测Vpr基因在靶细胞中的转录和表达情况,同时检测KSHV裂解期基因复制与转录激活子（Rta）mRNA转录及蛋白表达.结果经酶切鉴定、核酸序列测定和293T细胞中GFP表达证实成功包装了携带HIV-1Vpr基因的重组慢病毒,滴度为4×107TU/ml.重组慢病毒感染BCBL-1细胞后,细胞中有GFP表达,RT-PCR和Western blot均能够在相应位置检测到目的基因Vpr的条带,并且Vpr降低了KSHV RtamRNA转录及蛋白表达水平.结论重组慢病毒介导的HIV-1 Vpr蛋白过表达能够抑制KSHV裂解性复制、增强病毒的潜伏感染.

关键词：慢病毒病毒蛋白R 卡波济肉瘤相关疱疹病毒复制

High-resolution spatiotemporal mapping:a comprehensive view of eukaryotic cell cycle proteome dynamics

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Signal Transduction and Targeted Therapy 2024年第6期9卷 2354-2356页

作者： Jing Zou Ziran qin Long Zhang Life Sciences Institute Second Affiliated Hospital of the Zhejiang University School of MedicineThe MOE Key Laboratory of Biosystems Homeostasis&Protection and Zhejiang Provincial Key Laboratory for Cancer Molecular Cell BiologyZhejiang UniversityHangzhouZhejiangChina The MOE Basic Research and Innovation Center for the Targeted Therapeutics of Solid Tumors The First Affiliated HospitalJiangxi Medical CollegeNanchang UniversityNanchangChina Cancer Center Zhejiang UniversityHangzhouZhejiangChina

In a recent study published in Cell,Litsios et *** a highresolution spatiotemporal map of the eukaryotic cell cycle proteome.1 They identified proteome-level changes in both abundance and spatial distribution throughout the cell cycle and provided a valuable resource for future exploration into the global proteome dynamics that drive cell cycle progression(https://***/cellcycle).

关键词： al. cycle dynamics

Theoretical model of azimuthal combustion instability subject to non-trivial boundary conditions

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CHINESE JOURNAL OF AERONAUTICS 2024年第9期37卷 113-130页

作者： qin, Lei Wang, Xiaoyu Zhang, Guangyu Sun, Xiaofeng Beihang Univ Res Inst Aeroengine Beijing 100191 Peoples R China Beihang Univ Sch Energy & Power Engn Beijing 100191 Peoples R China

The problem of evaluating the sensitivity of non-trivial boundary conditions to the onset of azimuthal combustion instability is a longstanding challenge in the development process of modern gas turbines. The difficulty lies in how to describe three-dimensional in- and outlet boundary conditions in an artificial computational domain. To date, the existing analytical models have still failed to quantitatively explain why the features of the azimuthal combustion instability of a combustor in laboratory environment are quite different from that in a real gas turbine, making the stability control devices developed in laboratory generally lose the effectiveness in practical applications. To overcome this limitation, we provide a novel theoretical framework to directly include the effect of non-trivial boundary conditions on the azimuthal combustion instability. A key step is to take the non-trivial boundary conditions as equivalent distributed sources so as to uniformly describe the physical characteristics of the inner surface in an annular enclosure along with different in- and outlet configurations. Meanwhile, a dispersion relation equation is established by the application of three-dimensional Green's function approach and generalized impedance concept. Results show that the effects of the generalized modal reflection coefficients on azimuthal unstable modes are extremely prominent, and even prompt the transition from stable to unstable mode, thus reasonably explaining why the thermoacoustic instability phenomena in a real gas turbine are difficult to observe in an isolated combustion chamber. Overall, this work provides an effective tool for analysis of the azimuthal combustion instability including various complicated boundary conditions.

关键词： Combustion instability Aeroacoustics Modeling Optimization techniques Control SOUND-TRANSMISSION CALCULATIONS ACTUATOR diSK MODEL RAdiATION IMPEDANCES ACOUSTIC RAdiATION ACTIVE CONTROL BLADE ROW DUCT STABILITY PROPAGATION TURBOMACHINERY