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| 1 | Improved CICA Algorithm Used for Single Channel Compound Fault Diagnosis of Rolling Bearings显示文摘A Compound fault signal usually contains multiple characteristic signals and strong confusion noise, which makes it difficult to separate week fault signals from them through conventional ways, such as FFT-based envelope detection, wavelet transform or empirical mode decomposition individually. In order to realize single channel compound fault diagnosis of bearings and improve the diagnosis accuracy, an improved CICA algorithm named constrained independent component analysis based on the energy method(E-CICA) is proposed. With the approach, the single channel vibration signal is firstly decomposed into several wavelet coefficients by discrete wavelet transform(DWT) method for the purpose of obtaining multichannel signals. Then the envelope signals of the reconstructed wavelet coefficients are selected as the input of E-CICA algorithm, which fulfills the requirements that the number of sensors is greater than or equal to that of the source signals and makes it more suitable to be processed by CICA strategy. The frequency energy ratio(ER) of each wavelet reconstructed signal to the total energy of the given synchronous signal is calculated, and then the synchronous signal with maximum ER value is set as the reference signal accordingly. By this way, the reference signal contains a priori knowledge of fault source signal and the influence on fault signal extraction accuracy which is caused by the initial phase angle and the duty ratio of the reference signal in the traditional CICA algorithm is avoided. Experimental results show that E-CICA algorithm can effectively separate out the outer-race defect and the rollers defect from the single channel compound fault and fulfill the needs of compound fault diagnosis of rolling bearings, and the running time is 0.12% of that of the traditional CICA algorithm and the extraction accuracy is 1.4 times of that of CICA as well. The proposed research provides a new method to separate single channel compound fault signals. | CHEN Guohua QIE Longfei ZHANG Aijun HAN Jin | 2016 | Chinese Journal of Mechanical Engineering2016，29，1： | 12 |
| 2 | Presence of carboxylate salts in marine carbonate strata of the Ordos Basin and their impact on hydrocarbon generation evaluation of low TOC, high maturity source rocks显示文摘The total organic carbon(TOC)in the marine source rock of the Ordos Basin mostly ranges from 0.2%to 0.5%.The industrial standard commonly states that the TOC value has to be no less than 0.5%(0.4%for high mature or over-mature source rock)to form large petroleum reservoirs.However,gas source correlation indicates that the natural gas in the Jingbian gas field does receive contribution from marine source rocks.In order to determine the effect of carboxylate salts(or called as organic acid salts)on TOC in highly mature source rocks with low TOC value,we sampled the Ordovician marine source rock and the Permian transitional facies source rock in one drilled well in the southern Ordos Basin and performed infrared and GC-MS analysis.It is found that both kerogen-derived organic acids and carboxylate salt-conversed organic acids exist in both marine and transitional facies source rocks.The carboxylate salt-conversed organic acids mainly come from the complete acidification of carboxylate salts,which confirms the presence of carboxylate salts in the marine source rocks.Although the C16:O peak is the main peak for the organic acids both before and after acidification,the carboxylate salt-conversed organic acids have much less relative abundance ahead of C16:O compared with that of the kerogen-based and free organic acids.This observation suggests that the kerogen-based and free organic acids mainly decarboxylate to form lower carboxylic acids,whereas the carboxylate salt-conversed organic acids mainly break down into paraffins.By using calcium hexadecanoate as the reference to quantify the kerogen-derived and carboxylate salt-conversed organic acids,the high TOC(>2.0%)marine source rocks have low carboxylate salt content and the low TOC(0.2%–0.5%)marine source rocks contain high content of carboxylate salt.Therefore,for the marine source rocks with 0.2%–0.5%TOC,the carboxylate salts may be a potential gas source at high maturity stage. | LIU QuanYou JIN ZhiJun LIU WenHui LU LongFei MENG QianXiang TAO Ye HAN PinLong | 2013 | Science China Earth Sciences2013，56，12： | 9 |
| 3 | LIN28 coordinately promotes nucleolar/ribosomal functions and represses the 2C-like transcriptional program in pluripotent stem cells显示文摘LIN28 is an RNA binding protein with important roles in early embryo development,stem cell differentiation/re-programming,tumorigenesis and metabolism.Previous studies have focused mainly on its role in the cytosol where it interacts with Let-7 microRNA precursors or mRNAs,and few have addressed LIN28's role within the nucleus.Here,we show that LIN28 displays dynamic temporal and spatial expression during murine embryo development.Maternal LIN28 expression drops upon exit from the 2-cell stage,and zygotic LIN28 protein is induced at the forming nucleolus during 4-cell to blas-tocyst stage development,to become dominantly expressed in the cytosol after implantation.In cultured pluripotent stem cells(PSCs),loss of LIN28 led to nucleolar stress and activation of a 2-cell/4-cell-like transcriptional program characterized by the expression of endogenous retrovirus genes.Mechanistically,LIN28 binds to small nucleolar RNAs and rRNA to maintain nucleolar integrity,and its loss leads to nucleolar phase separation defects,ribosomal stress and activation of P53 which in turn binds to and activates 2C transcription factor Dux.LIN28 also resides in a complex containing the nucleolar factor Nucleolin(NCL)and the transcrip-tional repressor TRIM28,and LIN28 loss leads to reduced occupancy of the NCL/TRIM28 complex on the Dux and rDNA loci,and thus de-repressed Dux and reduced rRNA expression.Lin28 knockout cells with nucleolar stress are more likely to assume a slowly cycling,translationally inert and anabolically inactive state,which is a part of previously unappreciated 2C-like transcriptional program.These findings elucidate novel roles for nucleolar LIN28 in PSCs,and a new mechanism linking 2C program and nucleolar functions in PSCs and early embryo development. | Zhen Sun Hua Yu Jing Zhao Tianyu Tan Hongru Pan Yuqing Zhu Lang Chen Cheng Zhang Li Zhang Anhua Lei Yuyan Xu Xianju Bi Xin Huang Bo Gao Longfei Wang Cristina Correia Ming Chen Qiming Sun Yu Feng Li Shen Hao Wu Jianlong Wang Xiaohua Shen George Q.Daley Hu Li Jin Zhang | 2022 | Protein & Cell2022，13，7： | 4 |
| 4 | Temperature-dependent evolution of surface charge screening and polarization at ferroelectric surfaces显示文摘The polarization and domain behavior on the surface of a ferroelectric material are significantly affected by the screening processes [1-12].Recently,there has been a notable increase in the theoretical calculations and experiments investigating the dynamics of polarization and domain behaviors coexisting in phase transitions of ferroelectric materials. | LongFei Wang Yi Luo JieSu Wang XiuShi Huang ZhaoMeng Gao TieYing Yang XiaoLong Li Pei Li KuiJuan Jin WeiFeng Zhang HaiZhong Guo | 2019 | Science China(Physics,Mechanics & Astronomy)2019，62，8： | 3 |
| 5 | Aluminum hydride for solid-state hydrogen storage:Structure,synthesis, thermodynamics, kinetics, and regeneration显示文摘Aluminum hydride(AlH3) is a binary metal hydride that contains more than 10.1 wt% of hydrogen and possesses a high volumetric hydrogen density of 148 kg H2 m^(-3).Pristine AlH3 can readily release hydrogen at a moderate temperature below 200℃.Such high hydrogen density and low desorption temperature make AlH3 one of most promising hydrogen storage media for mobile application.This review covers the research activity on the structures,synthesis,decomposition thermodynamics and kinetics,regeneration and application validation of AlH3 over the past decades.Finally,the future research directions of AlH3 as a hydrogen storage material will be revealed. | Haizhen Liu Longfei Zhang Hongyu Ma Chenglin Lu Hui Luo Xinhua Wang Xiantun Huang Zhiqiang Lan Jin Guo | 2021 | Journal of Energy Chemistry2021，30，1： | 2 |
| 6 | Phase diagram of the ternary system lauric acid-capric acid-naphthalene 显示文摘 | JIN Longfei XIAO Fengping | 2004 | Thermochimica Acta2004，424，12： | 1 |
| 7 | Phase diagram of the ternary systern lauric acid-capric acid-naphthalene显示文摘 | Jin Longfei Xiao Feng-ping | 2004 | Thermochimica Acta2004，424，12： | 1 |
| 8 | AgPdCo hollow nanospheres electrocatalyst with high activity and stability toward the formate electrooxidation显示文摘The widespread commercial application of direct formate fuel cell(DFFC)is limited by the lack of efficient electrocatalysts for the formate oxidation reaction(FOR).AgPdCo hollow nanospheres(H-NSs)with jagged surfaces are successfully synthesized via a facile method involving the wet-chemical synthesis of AgPdCo nanospheres(NSs)and galvanic replacement reaction between Pd salt and AgPdCo NSs.Surpassing Ag_(30)Pd_(69)Co_(1) NSs and most of previously reported electrocatalysts,Ag_(9)Pd_(90)Co_(1) H-NSs exhibit extremely high FOR activity with a peak current density of 3.08 A·mg_(Pd)^(−1).Apart from the competitive activity,Ag_(9)Pd_(90)Co_(1) H-NSs show greatly improved chronoamperometric and cycling stability,whereby the current density retains about 0.24 A·mg_(Pd)^(−1) after 3,600 s electrocatalysis and the mass activity maintains 54.06%of the initial value after 500 cycles.The unique hollow nanosphere and synergistic effect are responsible for the enhanced activity and stability.This study will provide new clues for the development of outstanding electrocatalysts. | Qiao Wang Fuyi Chen Quan Tang Longfei Guo Tao Jin Bowei Pan Junpeng Wang Zhen Li Bo Kou Weiqi Bian | 2021 | Nano Research2021，14，7： | 1 |
| 9 | Approaching 19%efficiency and stable binary polymer solar cells enabled by a solidification strategy of solvent additive显示文摘Additives play a crucial role in enhancing the photovoltaic performance of polymer solar cells(PSCs).However,the typical additives used to optimize blend morphology of PSCs are still high boiling-point solvents,while their trace residues may reduce device stability.Herein,an effective strategy of“solidification of solvent additive(SSA)”has been developed to convert additive from liquid to solid,by introducing a covalent bond into low-cost solvent diphenyl sulfide(DPS)to synthesize solid dibenzothiophene(DBT)in one-step,which achieves optimized morphology thus promoting efficiency and device stability.Owing to the fine planarity and volatilization of DBT,the DBT-processed films achieve ordered molecular crystallinity and suitable phase separation compared to the additive-free or DPS-treated ones.Importantly,the DBT-processed device also possesses improved light absorption,enhanced charge transport,and thus a champion efficiency of 17.9%is achieved in the PM6:Y6-based PSCs with an excellent additive component tolerance,reproducibility,and stability.Additionally,the DBT-processed PM6:L8-BO-based PSCs are further fabricated to study the universality of SSA strategy,offering an impressive efficiency approaching19%as one of the highest values in binary PSCs.In conclusion,this article developed a promising strategy named SSA to boost efficiency and improve stability of PSCs. | Manjun Xiao Longfei Liu Yongdie Meng Baobing Fan Wenyan Su Conggui Jin Luocheng Liao Fan Yi Chao Xu Rui Zhang Alex K.-Y.Jen Wei Ma Qunping Fan | 2023 | Science China Chemistry2023，66，5： | 1 |
| 10 | FMECA and FTA Methods of Reliability Analysis for Oil and Gas Pipeline Robot显示文摘In this paper,FMECA and FTA methods are presented for oil and gas Pipeline Robot in order to improve the reliability.Take a crawler pipeline cleaning robot as the research object.According to the robot′s variable working environment,high failure rate and short service life,in order to reduce the probability of its failure,and to extend its use time limit under the premise of being able to adapt to the complex working environment,and reduce maintenance cost of failure.To realize this purpose,FMECA analysis is fristly proposed,by which obtain the failure modes,causes and effects of each component mechanism,and identify the component mechanism with high risk and failure rate.Secondly,FTA is developed to establish the fault tree model of Cleaning and diameter changing mechanism,retain the underlying fault and the cause of its failure.Simulation results are carried out to illustrate the effectiveness of this proposed method and improvement measures to improve the reliability of the robot. | SONG Jin ZHANG Xiaolong LUO Ying HUANG Kuang LIU Jie WU Longfei | 2021 | International Journal of Plant Engineering and Management2021，26，4： | 1 |
| 11 | Iron( III ) coordination induced novel 18-rnetallacrown-6 complex: esterification and isolation of the ligand 显示文摘 | Jin Longfei Yu Hui Wu Shuxiang | 2009 | Dalton Trans2009，，： | 1 |
| 12 | Novel dual inhibitors against FP-2 and PfDHFR as potential antimalarial agents: Design, synthesis and biological evaluation显示文摘Resistance to malaria parasites has quickly developed to almost all used antimalarial drugs. Cysteine protease falcipain-2(FP-2) and Plasmodium falciparum dihydrofolate reductase(PfDHFR) have crucial roles, which are absolutely necessary, in the parasite life cycle. In this study, based on the uniform pharmacophores of reported PfDHFR inhibitors and the first-generation dual inhibitors against FP-2 and PfDHFR, we identified a novel series of dual inhibitors through fragments assembly. Lead optimization led to the identification of 14, which showed potent inhibition against FP-2 and PfDHFR enzyme(IC_(50)= 6.8 + 1.8 mmol/L and IC_(50)= 8.8 + 0.3 mmol/L) and P. falciparum 3D7 strain(IC50= 2.9mmol/L).Additionally, 14 exhibited more potent inhibition to the proliferation of chloroquine-resistant P.falciparum Dd2 strain(IC_(50)= 1.1 mmol/L) than pyrimethamine(IC_(50)>10 mmol/L), and 14 displayed micromolar inhibitory activities against two clinical isolated strains Fab9(IC_(50)= 2.6 mmol/L) and GB4(IC_(50)= 1.0 mmol/L). Collectively, these data demonstrated that 14 might be a good lead compound for the treatment of malaria. | Wenhua Chen Xue Yao Zhenghui Huang Fei Mao Longfei Guan Yun Tang Hualiang Jiang Jian Li Jin Huang Lubin Jiang Jin Zhu | 2019 | Chinese Chemical Letters2019，30，1： | 0 |
| 13 | Multi-scale simulation model of air system based on cross-dimensional data transmission method显示文摘The Secondary Air System(SAS)plays an important role in the safe operation and performance of aeroengines.The traditional 1D-3D coupling method loses information when used for secondary air systems,which affects the calculation accuracy.In this paper,a Cross-dimensional Data Transmission method(CDT)from 3D to 1D is proposed by introducing flow field uniformity into the data transmission.First,a uniformity index was established to quantify the flow field parameter distribution characteristics,and a uniformity index prediction model based on the locally weighted regression method(Lowess)was established to quickly obtain the flow field information.Then,an information selection criterion in 3D to 1D data transmission was established based on the Spearman rank correlation coefficient between the uniformity index and the accuracy of coupling calculation,and the calculation method was automatically determined according to the established criterion.Finally,a modified function was obtained by fitting the ratio of the 3D mass-average parameters to the analytical solution,which are then used to modify the selected parameters at the 1D-3D interface.Taking a typical disk cavity air system as an example,the results show that the calculation accuracy of the CDT method is greatly improved by a relative 53.88%compared with the traditional 1D-3D coupling method.Furthermore,the CDT method achieves a speedup of 2 to 3 orders of magnitude compared to the 3D calculation. | Lei WANG Junkui MAO Song WEI Longfei WANG Jin PAN | 2023 | Chinese Journal of Aeronautics2023，36，5： | 0 |
| 14 | TECMH:Transformer-Based Cross-Modal Hashing For Fine-Grained Image-Text Retrieval显示文摘In recent years,cross-modal hash retrieval has become a popular research field because of its advantages of high efficiency and low storage.Cross-modal retrieval technology can be applied to search engines,crossmodalmedical processing,etc.The existing main method is to use amulti-label matching paradigm to finish the retrieval tasks.However,such methods do not use fine-grained information in the multi-modal data,which may lead to suboptimal results.To avoid cross-modal matching turning into label matching,this paper proposes an end-to-end fine-grained cross-modal hash retrieval method,which can focus more on the fine-grained semantic information of multi-modal data.First,the method refines the image features and no longer uses multiple labels to represent text features but uses BERT for processing.Second,this method uses the inference capabilities of the transformer encoder to generate global fine-grained features.Finally,in order to better judge the effect of the fine-grained model,this paper uses the datasets in the image text matching field instead of the traditional label-matching datasets.This article experiment on Microsoft COCO(MS-COCO)and Flickr30K datasets and compare it with the previous classicalmethods.The experimental results show that this method can obtain more advanced results in the cross-modal hash retrieval field. | Qiqi Li Longfei Ma Zheng Jiang Mingyong Li Bo Jin | 2023 | Computers, Materials & Continua2023，，5： | 0 |
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