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Engineering the spectra of photon triplets generated from micro/nanofiber
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作者 瞿川 郭东琴 +4 位作者 李笑笑 刘振旗 赵义 张胜海 卫正统 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期408-414,共7页
Quantum light sources are the core resources for photonics-based quantum information processing.We investigate the spectral engineering of photon triplets generated by third-order spontaneous parametric down-conversio... Quantum light sources are the core resources for photonics-based quantum information processing.We investigate the spectral engineering of photon triplets generated by third-order spontaneous parametric down-conversion in micro/nanofiber.The phase mismatching at one-third pump frequency gives rise to non-degenerate photon triplets,the joint spectral intensity of which has an elliptical locus with a fixed eccentricity of√6/3.Therefore,we propose a frequency-division scheme to separate non-degenerate photon triplets into three channels with high heralding efficiency for the first time.Choosing an appropriate pump wavelength can compensate for the fabrication errors of micro/nanofiber and also generate narrowband,non-degenerate photon triplet sources with a high signal-to-noise ratio.Furthermore,the long-period micro/nanofiber grating introduces a new controllable degree of freedom to tailor phase matching,resulting from the periodic oscillation of dispersion.In this scheme,the wavelength of photon triplets can be flexibly tuned using quasi-phase matching.We study the generation of photon triplets from this novel perspective of spectrum engineering,and we believe that this work will accelerate the practical implementation of photon triplets in quantum information processing. 展开更多
关键词 photon triplets micro/nanofiber spectrum engineering
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Improved multi-scale inverse bottleneck residual network based on triplet parallel attention for apple leaf disease identification
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作者 Lei Tang Jizheng Yi Xiaoyao Li 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第3期901-922,共22页
Accurate diagnosis of apple leaf diseases is crucial for improving the quality of apple production and promoting the development of the apple industry. However, apple leaf diseases do not differ significantly from ima... Accurate diagnosis of apple leaf diseases is crucial for improving the quality of apple production and promoting the development of the apple industry. However, apple leaf diseases do not differ significantly from image texture and structural information. The difficulties in disease feature extraction in complex backgrounds slow the related research progress. To address the problems, this paper proposes an improved multi-scale inverse bottleneck residual network model based on a triplet parallel attention mechanism, which is built upon ResNet-50, while improving and combining the inception module and ResNext inverse bottleneck blocks, to recognize seven types of apple leaf(including six diseases of alternaria leaf spot, brown spot, grey spot, mosaic, rust, scab, and one healthy). First, the 3×3 convolutions in some of the residual modules are replaced by multi-scale residual convolutions, the convolution kernels of different sizes contained in each branch of the multi-scale convolution are applied to extract feature maps of different sizes, and the outputs of these branches are multi-scale fused by summing to enrich the output features of the images. Second, the global layer-wise dynamic coordinated inverse bottleneck structure is used to reduce the network feature loss. The inverse bottleneck structure makes the image information less lossy when transforming from different dimensional feature spaces. The fusion of multi-scale and layer-wise dynamic coordinated inverse bottlenecks makes the model effectively balances computational efficiency and feature representation capability, and more robust with a combination of horizontal and vertical features in the fine identification of apple leaf diseases. Finally, after each improved module, a triplet parallel attention module is integrated with cross-dimensional interactions among channels through rotations and residual transformations, which improves the parallel search efficiency of important features and the recognition rate of the network with relatively small computational costs while the dimensional dependencies are improved. To verify the validity of the model in this paper, we uniformly enhance apple leaf disease images screened from the public data sets of Plant Village, Baidu Flying Paddle, and the Internet. The final processed image count is 14,000. The ablation study, pre-processing comparison, and method comparison are conducted on the processed datasets. The experimental results demonstrate that the proposed method reaches 98.73% accuracy on the adopted datasets, which is 1.82% higher than the classical ResNet-50 model, and 0.29% better than the apple leaf disease datasets before preprocessing. It also achieves competitive results in apple leaf disease identification compared to some state-ofthe-art methods. 展开更多
关键词 multi-scale module inverse bottleneck structure triplet parallel attention apple leaf disease
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Triplet Label Based Image Retrieval Using Deep Learning in Large Database 被引量:1
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作者 K.Nithya V.Rajamani 《Computer Systems Science & Engineering》 SCIE EI 2023年第3期2655-2666,共12页
Recent days,Image retrieval has become a tedious process as the image database has grown very larger.The introduction of Machine Learning(ML)and Deep Learning(DL)made this process more comfortable.In these,the pair-wi... Recent days,Image retrieval has become a tedious process as the image database has grown very larger.The introduction of Machine Learning(ML)and Deep Learning(DL)made this process more comfortable.In these,the pair-wise label similarity is used tofind the matching images from the database.But this method lacks of limited propose code and weak execution of misclassified images.In order to get-rid of the above problem,a novel triplet based label that incorporates context-spatial similarity measure is proposed.A Point Attention Based Triplet Network(PABTN)is introduced to study propose code that gives maximum discriminative ability.To improve the performance of ranking,a corre-lating resolutions for the classification,triplet labels based onfindings,a spatial-attention mechanism and Region Of Interest(ROI)and small trial information loss containing a new triplet cross-entropy loss are used.From the experimental results,it is shown that the proposed technique exhibits better results in terms of mean Reciprocal Rank(mRR)and mean Average Precision(mAP)in the CIFAR-10 and NUS-WIPE datasets. 展开更多
关键词 Image retrieval deep learning point attention based triplet network correlating resolutions classification region of interest
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Landmarks-Driven Triplet Representation for Facial Expression Similarity
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作者 周逸润 冯向阳 朱明 《Journal of Donghua University(English Edition)》 CAS 2023年第1期34-44,共11页
The facial landmarks can provide valuable information for expression-related tasks.However,most approaches only use landmarks for segmentation preprocessing or directly input them into the neural network for fully con... The facial landmarks can provide valuable information for expression-related tasks.However,most approaches only use landmarks for segmentation preprocessing or directly input them into the neural network for fully connection.Such simple combination not only fails to pass the spatial information to network,but also increases calculation amounts.The method proposed in this paper aims to integrate facial landmarks-driven representation into the triplet network.The spatial information provided by landmarks is introduced into the feature extraction process,so that the model can better capture the location relationship.In addition,coordinate information is also integrated into the triple loss calculation to further enhance similarity prediction.Specifically,for each image,the coordinates of 68 landmarks are detected,and then a region attention map based on these landmarks is generated.For the feature map output by the shallow convolutional layer,it will be multiplied with the attention map to correct the feature activation,so as to strengthen the key region and weaken the unimportant region.Finally,the optimized embedding output can be further used for downstream tasks.Three embeddings of three images output by the network can be regarded as a triplet representation for similarity computation.Through the CK+dataset,the effectiveness of such an optimized feature extraction is verified.After that,it is applied to facial expression similarity tasks.The results on the facial expression comparison(FEC)dataset show that the accuracy rate will be significantly improved after the landmark information is introduced. 展开更多
关键词 facial expression similarity facial landmark triplet network attention mechanism feature optimization
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Four-Electron Systems in the Impurity Hubbard Model. Second Triplet State. Spectra of the System in the ν-Dimensional Lattice Zν
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作者 S. M. Tashpulatov R. T. Parmanova 《Journal of Applied Mathematics and Physics》 2023年第11期3393-3427,共35页
We consider an energy operator of four-electron system in the Impurity Hubbard model with a coupling between nearest-neighbors. The spectrum of the systems in the second triplet state in a ν-dimensional lattice is in... We consider an energy operator of four-electron system in the Impurity Hubbard model with a coupling between nearest-neighbors. The spectrum of the systems in the second triplet state in a ν-dimensional lattice is investigated. For investigation the structure of essential spectra and discrete spectrum of the energy operator of four-electron systems in an impurity Hubbard model, for which the momentum representation is convenient. In addition, we used the tensor products of Hilbert spaces and tensor products of operators in Hilbert spaces and described the structure of essential spectrum and discrete spectrum of the energy operator of four-electron systems in an impurity Hubbard model for the second triplet state of the system. The investigations show that the essential spectrum of the system consists of the union of no more than sixteen segments, and the discrete spectrum of the system consists of no more than eleven eigenvalues. 展开更多
关键词 Spectra of Four-Electron System Bound State Anti-Bound State Impurity Hubbard Model Quintet State Singlet State triplet State
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Spontaneous Monochorionic Triamniotic Triplet Pregnancy: A Case Report
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作者 Al Hussain Al Hazmi Ola Tayeb +1 位作者 Afrah Al Mutairi Mufareh Asiri 《Open Journal of Obstetrics and Gynecology》 2023年第6期1075-1080,共6页
Background: Monochorionic triamniotic (MCTA) triplet pregnancy is a rare entity associated with a high risk of complications. In most previously reported cases, the pregnancy was conceived with the use of assisted rep... Background: Monochorionic triamniotic (MCTA) triplet pregnancy is a rare entity associated with a high risk of complications. In most previously reported cases, the pregnancy was conceived with the use of assisted reproductive technologies, and these cases were associated with complications. Case Presentation: We report a 28-year-old woman with a spontaneously conceived MCTA triplet pregnancy diagnosed at the gestational age of 26 weeks. All fetuses had normal amniotic fluid and umbilical artery Doppler findings were normal. The estimated weight of fetuses was 848 g, 891 g, and 1 kg, respectively. The patient was managed conservatively with a plan to monitor fetal growth every two weeks and a Doppler study twice weekly. On the 8<sup>th</sup> day of admission, the patient developed labor pains. Per vaginal examination revealed 1 - 2 cm cervical dilatation. Cesarean section was performed, and three girls were delivered with a single placenta (birth weight: 820, 925, and 960 g, respectively). Conclusion: Monochorionic triplet pregnancy is associated with a higher risk of fetal morbidity and mortality. Therefore, awareness of its complications can facilitate better management of such cases. 展开更多
关键词 Monochorionic Triamniotic triplet Pregnancy Case Report
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基于Triplet注意力的循环卷积神经网络模型
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作者 汪璟玢 雷晶 +1 位作者 张璟璇 孙首男 《模式识别与人工智能》 EI CSCD 北大核心 2022年第2期116-129,共14页
现有的融合文本或邻居信息的知识补全模型忽略文本和邻居之间的相互作用,难以捕获与实体具有较强语义相关性的信息,加上基于卷积神经网络的模型未考虑实体中的关系相关信息,导致预测性能不佳.因此,文中结合文本信息和拓扑邻居信息,提出... 现有的融合文本或邻居信息的知识补全模型忽略文本和邻居之间的相互作用,难以捕获与实体具有较强语义相关性的信息,加上基于卷积神经网络的模型未考虑实体中的关系相关信息,导致预测性能不佳.因此,文中结合文本信息和拓扑邻居信息,提出基于Triplet注意力的循环卷积神经网络模型.首先,通过语义匹配的方式,选取文本描述中与实体具有较强语义相关性的单词.再与拓扑邻居复合作为实体邻居,增强实体表示.然后,重塑实体的融合表示和关系表示.最后,利用Triplet注意力优化卷积输入,使卷积操作能提取实体中与关系相关的特征,提升模型性能.在多个公开数据集上的链路预测实验表明,文中模型性能较优. 展开更多
关键词 知识图谱补全 文本信息 拓扑邻居 循环卷积 triplet注意力
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基于Triplet loss的电磁阀故障识别方法 被引量:2
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作者 张文啸 孟国香 叶骞 《液压与气动》 北大核心 2022年第9期116-125,共10页
针对电磁阀故障识别对专家知识依赖过高,现有智能诊断系统多需要人为提取信号特征等问题,以某型号电磁阀作为研究对象,人为设置故障工况,采集各种工况下的多通道运行数据,利用TensorFlow平台搭建了对该电磁阀的端对端故障识别模型。此外... 针对电磁阀故障识别对专家知识依赖过高,现有智能诊断系统多需要人为提取信号特征等问题,以某型号电磁阀作为研究对象,人为设置故障工况,采集各种工况下的多通道运行数据,利用TensorFlow平台搭建了对该电磁阀的端对端故障识别模型。此外,在此基础上又提出了基于Triplet loss函数的改进模型,并进行了验证测试。结果表明,基于Triplet loss的故障识别模型除具有更高的识别准确率之外,对于在不同动作频率下工作的电磁阀信号有更好的泛化能力。 展开更多
关键词 电磁阀 故障识别 机器学习 triplet loss TensorFlow
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Properties,combustion behavior,and kinetic triplets of coke produced by low-temperature oxidation and pyrolysis:Implications for heavy oil in-situ combustion 被引量:4
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作者 Shuai Zhao Wan-Fen Pu +6 位作者 Lei Su Ce Shang Yang Song Wei Li Hui-Zhuo He Yi-Gang Liu Zhe-Zhi Liu 《Petroleum Science》 SCIE CAS CSCD 2021年第5期1483-1491,共9页
This work aimed at investigating the crucial factor in building and maintaining the combustion front during in-situ combustion(ISC),oxidized coke and pyrolyzed coke.The surface morphologies,elemental contents,and non-... This work aimed at investigating the crucial factor in building and maintaining the combustion front during in-situ combustion(ISC),oxidized coke and pyrolyzed coke.The surface morphologies,elemental contents,and non-isothermal mass losses of the oxidized and pyrolyzed cokes were thoroughly examined.The results indicated that the oxidized coke could be combusted at a lower temperature compared to the pyrolyzed coke due primarily to their differences in the molecular polarity and microstructure.Kinetic triplets of coke combustion were determined using iso-conversional models and one advanced integral master plots method.The activation energy values of the oxidized and pyrolyzed cokes varied in the range of 130-153 k J/mol and 95-120 kJ/mol,respectively.The most appropriate reaction model of combustion of the oxidized and pyrolyzed cokes followed three-dimensional diffusion model(D_(3)) and random nucleation and subsequent growth model(F_(1)),respectively.These observations assisted in building the numerical model of these two types of cokes to simulate the ISC process. 展开更多
关键词 Oxidized coke Pyrolyzed coke Heavy oil In-situ combustion Kinetic triplets
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Tunneling Conductance in Normal Metal/Insulator/Triplet Superconductor Junction 被引量:3
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作者 LI Xiao-Wei 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第2X期381-384,共4页
Tunneling conductance in normal metal/insulator/triplet superconductor junctions is studied theoretically as a function of the bias voltage at zero temperature and finite temperature. The results show there are zero-b... Tunneling conductance in normal metal/insulator/triplet superconductor junctions is studied theoretically as a function of the bias voltage at zero temperature and finite temperature. The results show there are zero-bias conductance peak, zero-bias conductance dip and double-minimum structures in the spectra for p-wave superconductor junctions. The existence of such structures in the conductance spectrum can be taken as evidence that the pairing symmetry of Sr2RuO4 is p-wave symmetry. 展开更多
关键词 超导体 导电系数 p-波 有限温度
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Study on the Singlet and Triplet StateElectron Transfer between Hypocrellin A and Aromatic Amines in Solvents of Various Polarity 被引量:1
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作者 Min WENG ManHua ZHANG Tao SHEN(Institute of Photographic Chemistry, Academia Sinica, P.O.Box 772,Beijing 100101) 《Chinese Chemical Letters》 SCIE CAS CSCD 1996年第10期924-927,共4页
In this paper, the singlet and triplet state electron transfer processes between hypocrellin A(HA) and aromatic amines in solvents of various polarity have been studied by fluorescence and time-resolved transient abso... In this paper, the singlet and triplet state electron transfer processes between hypocrellin A(HA) and aromatic amines in solvents of various polarity have been studied by fluorescence and time-resolved transient absorption spectra. The results show,in.polar solvent, the quenching of HA fluorescence by aromatic amines results in Stern-Volmer plot, the investigation of transient absorption indicated that triplet-state electron transfer process from 3HA to the ground-state of amines occured, and the wines of the singlet and triplet state electron transfer rate constant were calculated, however in weak polar solvent, only the triplet-triplet absorption of HA was observed. 展开更多
关键词 StateElectron TRANSFER triplet Solvents VARIOUS HYPOCRELLIN
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Coupled Cross-correlation Neural Network Algorithm for Principal Singular Triplet Extraction of a Cross-covariance Matrix 被引量:2
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作者 Xiaowei Feng Xiangyu Kong Hongguang Ma 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI 2016年第2期149-156,共8页
This paper proposes a novel coupled neural network learning algorithm to extract the principal singular triplet(PST)of a cross-correlation matrix between two high-dimensional data streams. We firstly introduce a novel... This paper proposes a novel coupled neural network learning algorithm to extract the principal singular triplet(PST)of a cross-correlation matrix between two high-dimensional data streams. We firstly introduce a novel information criterion(NIC),in which the stationary points are singular triplet of the crosscorrelation matrix. Then, based on Newton's method, we obtain a coupled system of ordinary differential equations(ODEs) from the NIC. The ODEs have the same equilibria as the gradient of NIC, however, only the first PST of the system is stable(which is also the desired solution), and all others are(unstable)saddle points. Based on the system, we finally obtain a fast and stable algorithm for PST extraction. The proposed algorithm can solve the speed-stability problem that plagues most noncoupled learning rules. Moreover, the proposed algorithm can also be used to extract multiple PSTs effectively by using sequential method. 展开更多
关键词 Singular value decomposition(SVD) coupled algorithm cross-correlation neural network(CNN) speed-stability problem principal singular subspace(PSS) principal singular triplet(PST)
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Prognostic significance of peritoneal metastasis from colorectal cancer treated with first-line triplet chemotherapy 被引量:1
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作者 Shouki Bazarbashi Abdulrahman Alghabban +3 位作者 Mohamed Aseafan Ali H Aljubran Ahmed Alzahrani Tusneem AM Elhassan 《World Journal of Clinical Cases》 SCIE 2022年第8期2429-2438,共10页
BACKGROUND Peritoneal metastasis from colorectal cancer(CRC)carries a poor prognosis in most studies.The majority of those studies used either a single-agent or doublet chemotherapy regimen in the first-line setting.A... BACKGROUND Peritoneal metastasis from colorectal cancer(CRC)carries a poor prognosis in most studies.The majority of those studies used either a single-agent or doublet chemotherapy regimen in the first-line setting.AIM To investigate the prognostic significance of peritoneal metastasis in a cohort of patients treated with triplet chemotherapy in the first-line setting.METHODS We retrospectively evaluated progression-free survival(PFS)and overall survival(OS)in 51 patients with metastatic CRC treated in a prospective clinical trial with capecitabine,oxaliplatin,irinotecan,and bevacizumab in the first-line setting according to the presence and absence of peritoneal metastasis.Furthermore,univariate and multivariate analyses for PFS and OS were performed to assess the prognostic significance of peritoneal metastasis at the multivariate level.RESULTS Fifty-one patients were treated with the above triplet therapy.Fifteen had peritoneal metastasis.The patient characteristics of both groups showed a significant difference in the sidedness of the primary tumor(left-sided primary tumor in 60%of the peritoneal group vs 86%in the nonperitoneal group,P=0.03)and the presence of liver metastasis(40%for the peritoneal group vs 75%for the nonperitoneal group,P=0.01).Univariate analysis for PFS showed a statistically significant difference for age less than 65 years(P=0.034),presence of liver metastasis(P=0.046),lung metastasis(P=0.011),and those who underwent metastasectomy(P=0.001).Only liver metastasis and metastasectomy were statistically significant for OS,with P values of 0.001 and 0.002,respectively.Multivariate analysis showed that age(less than 65 years)and metastasectomy were statistically significant for PFS,with P values of 0.002 and 0.001,respectively.On the other hand,the absence of liver metastasis and metastasectomy were statistically significant for OS,with P values of 0.003 and 0.005,respectively.CONCLUSION Peritoneal metastasis in patients with metastatic CRC treated with first-line triple chemotherapy does not carry prognostic significance at univariate and multivariate levels.Confirmatory larger studies are warranted. 展开更多
关键词 Colorectal cancer Peritoneal carcinomatosis triplet chemotherapy Survival Prognostic factors METASTASECTOMY
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Spectra of the Energy Operator of Four-Electron Systems in the Impurity Hubbard Model. Triplet State 被引量:1
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作者 S. M. Tashpulatov R. T. Parmanova 《Journal of Applied Mathematics and Physics》 2021年第11期2776-2795,共20页
We consider the energy operator of four-electron systems in an impurity Hubbard model and investigated the structure of essential spectra and discrete spectrum of the system in the first triplet state in a one-dimensi... We consider the energy operator of four-electron systems in an impurity Hubbard model and investigated the structure of essential spectra and discrete spectrum of the system in the first triplet state in a one-dimensional lattice. For investigation the structure of essential spectra and discrete spectrum of the energy operator of four-electron systems in an impurity Hubbard model, for which the momentum representation is convenient. In addition, we used the tensor products of Hilbert spaces and tensor products of operators in Hilbert spaces and described the structure of essential spectrum and discrete spectrum of the energy operator of four-electron systems in an impurity Hubbard model. The investigations show that there are such cases: 1) the essential spectrum of the system consists of the union of no more than eight segments, and the discrete spectrum of the system consists of no more than three eigenvalues;2) the essential spectrum of the system consists of the union of no more than sixteen segments, and the discrete spectrum of the system consists of no more than eleven eigenvalues;3) the essential spectrum of the system consists of the union of no more than three segments, and the discrete spectrum of the system is the empty set. Consequently, the essential spectrum of the system consists of the union of no more than sixteen segments, and the discrete spectrum of the system consists of no more than eleven eigenvalues. 展开更多
关键词 Hubbard Model Essential Spectrum Discrete Spectrum Four Electron Systems Quintet State triplet State Singlet State SPECTRA
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On the Distribution of Prime-Triplets 被引量:1
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作者 Tu Xiangchu~1, Tu Chengyuan~2, Tu Chengyu~1(1.College of Electronic & Control Engineering, Beijing University of Technology, Beijing, 100022, China 2.College of Mechanical Engineering & Applied Electronic Technology, Beijing University of Technology, Beijing, 100022, China) 《工程科学(英文版)》 2007年第2期139-147,共9页
A new approach to the research of the distribution of prime-triplets is developed. It differs from the usual methods (involving the sieve method) for this kind of research, and basing on Chebyshev inequality and on th... A new approach to the research of the distribution of prime-triplets is developed. It differs from the usual methods (involving the sieve method) for this kind of research, and basing on Chebyshev inequality and on the computation of average concentration of all the related subset. It leads to the proofs of following Lemma 2 and Theorem 2 (Lemma 1 and Theorem 1 in Reference 1 had been proved by means of this new method): Lemma 2 Among all the prime-triplet-subsets there exists at least one such subset which is an infinite set. Theorem 2 All the prime-triplet-subsets or infinitely many such subsets are infinite sets.Formulas for estimating the amount of such infinite sets are provided in this paper. 展开更多
关键词 prime-triplet prime-triplet-subset CHEBYSHEV INEQUALITY average concentration
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PROBE FOR THE FORMATION RATIO BETWEEN EXCITED TRIPLETS AND SINGLETS AS GENERATED IN POLYMER LIGHT-EMITTING DIODES
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作者 Jing-ying Zhang Shi-dong Kan +1 位作者 Yu-guang Ma Jia-cong Shen Key Lab for Supramolecular Structure and Spectroscopy of Ministry of Education, Jilin University Changchun 130023, China 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2001年第6期591-596,共6页
The electroluminescence (EL) produced by a highly luminescent phosphorescent dye Cu-4(CdropCPh)(4)L-2 (L = 1.8-bis(di-phenylphosphino)-3,6-dioxaoctane, Cu-4) doped polymer as emitting layer is reported. The effects of... The electroluminescence (EL) produced by a highly luminescent phosphorescent dye Cu-4(CdropCPh)(4)L-2 (L = 1.8-bis(di-phenylphosphino)-3,6-dioxaoctane, Cu-4) doped polymer as emitting layer is reported. The effects of the charge injection balance on the polymers, in particular, poly(N-vinylcarbazole) (PVK) have been studied by using photoluminescence and electroluminescence spectroscopy. Changes in the emission spectra demonstrate the influence of the charge injection balance on the formation ratio of triplet and singlet excitons. This provides a new technical approach to realize the color patterning in polymer LEDs. 展开更多
关键词 ELECTROLUMINESCENCE organic polymer triplet exciton
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Synthesis and photochemistry of novel bromo substituted stilbene derivatives as triplet state sensitizers for the generation of singlet oxygen
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作者 Hong Ru Li Qin Yuan Guo Ting Xie Fang Gao Sheng Tao Zhang 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第12期1415-1418,共4页
We have presented the synthesis and characterization of three new bromo substituted stilbene derivatives, p-3,4,5-trimethoxy-p′- 2,3,4,5,6-pentabromostilbene (C1), p-N,N-dimethylamino-p′-2,3,4,5,6-pentabromostilbe... We have presented the synthesis and characterization of three new bromo substituted stilbene derivatives, p-3,4,5-trimethoxy-p′- 2,3,4,5,6-pentabromostilbene (C1), p-N,N-dimethylamino-p′-2,3,4,5,6-pentabromostilbene (C2) and p-N,N-diphenylamino-p′- 2,3,4,5,6-pentabromostilbene (C3) in this letter. The UV/vis absorption and photoluminescence were investigated in various solvents. The maximal absorption wavelength of C1 exhibited blue-shift to those of C2 and C3 in different solvents. No florescence emission could be detected for these compounds at room temperature. Singlet oxygen could be efficiently produced with these sensitizers under near-ultraviolet and visible light irradiation. 展开更多
关键词 SYNTHESIS PHOTOCHEMISTRY triplet state Bromo substitution Singlet oxygen
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Triangle Type Trinuclear Copper Complexes with Triplet-excitation Luminescent Property, an Ab Initio Study
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作者 MANG Chao-Yong ZHANG Ming-Xin WU Ke-Chen 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第5期517-522,共6页
The luminescent mechanism and properties of a triangular Cu(I) complex, (CuPz)3. have been studied by CIS method. The ground and lowest triplet excitation state geometries were optimized at MP2/SBKJC and CIS/SBKJC... The luminescent mechanism and properties of a triangular Cu(I) complex, (CuPz)3. have been studied by CIS method. The ground and lowest triplet excitation state geometries were optimized at MP2/SBKJC and CIS/SBKJC levels, respectively. A remarkable geometry distortion of the lowest triplet state was found and believed to cause the emission spectra to red shift. 展开更多
关键词 luminescence triplet excitation PHOSPHORESCENCE copper complex
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Vortex pinning and rectification effect in a nanostructured superconducting film with a square array of antidot triplets
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作者 何安 薛存 周又和 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第5期458-463,共6页
We study the stability of vortices pinning and dynamics in a superconducting thin strip containing a square array of antidot triplets by using the nonlinear Ginzburg–Landau(GL) theory. Compared with the regular squ... We study the stability of vortices pinning and dynamics in a superconducting thin strip containing a square array of antidot triplets by using the nonlinear Ginzburg–Landau(GL) theory. Compared with the regular square array of circular holes, the vortices are no longer pinned inside the circular holes, but instead stabilized at the center of the antidot triplets depending on the geometry parameters. Moreover, the influences of the geometry parameters and the polarity of the applied current on the current–voltage(I–V) characteristics are also studied. The critical current for the sample turning into a normal state becomes smaller when the hole diameter D is smaller and the spacing B between the holes is larger. Due to the asymmetric pinning sites, our numerical simulations demonstrate that the positive and negative rectified voltages appear alternately in the resistive state of the sample under an ac current of square pulses. 展开更多
关键词 matching effect antidot triplets current-voltage characteristic critical current
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Perturbation study via rotational-resolved in the triplet band d^3△- a^3П(2, 1) of spectrum CO
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作者 许春燕 杨晓华 +3 位作者 郭迎春 吴玲 李伟 陈扬骎 《Chinese Physics B》 SCIE EI CAS CSCD 2005年第10期1954-1959,共6页
The triplet band d^3△- a^3П (2, 1) of the CO molecule in the near infrared region of 12350-12850cm^-1 has been observed and analysed by taking into account the perturbation interaction between the d^3△ (v=2) an... The triplet band d^3△- a^3П (2, 1) of the CO molecule in the near infrared region of 12350-12850cm^-1 has been observed and analysed by taking into account the perturbation interaction between the d^3△ (v=2) and a^3П (v= 9) states. The most perturbed lines and most precise perturbation parameters, α2 and β2, and electronic perturbation constants, ξe and ηe, for the d^3△ (v= 2) and a^3П (v=9) states have been obtained. 展开更多
关键词 CO molecule triplet band PERTURBATION
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