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Effects of phase change material(PCM)-based nanocomposite additives on thermal decomposition and burning characteristic of high energy propellants containing RDX

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Defence Technology（防务技术） 2022年第4期18卷 557-566页

作者： En-fa Fu na Sun Zheng-gang Xiao Key Laboratory of Special Energy Materials Ministry of Education School of Chemical Engineering Nanjing University of Science and Technology

A kind of phase change material(PCM)-based nanocomposite was prepared and added into high energy propellants containing RDX as additives to investigate its effect on thermal decomposition and burning characteristic of high energy *** effect of PCM-based nanocomposites on thermal decomposition of high energy propellants is investigated by TG/DSC-FTIR-MS *** to the delayed protection effect(PCM-based nanocomposites can absorb lots of heat at the range of certain temperature when it undergoes structure change or phase transitions)of PCM-based nanocomposites under the thermal decomposition condition,the thermal stability of high energy propellants modified with PCMbased nanocomposites is *** the same time,the concentration of N2,NO2,H2O and CO_(2)is increased during thermal decomposition of high energy propellants whereas NO and CO is *** burning gaseous products and burning characteristic of high energy propellants are studied by the combination of closed bomb test and Fourier transform infrared *** main burning gaseous products are N2,CO_(2),CO,H2O,CH4,*** the high energy propellant modified with PCM-based nanocomposites,the concentration of CH4is increased while CO,CO_(2) and H2O is decreased under the high-pressure burning *** progressivity factor of high energy propellants is increased by22.2%compared with the control sample while the maximum pressure is merely decreased 1.25%after the addition of the PCM-based nanocomposite,thus PCM-based nanocomposites can be used to adjust the burning process and improve the burning progressivity of high energy *** study is expected to boost the practical application of PCM-based nanocomposite to the propellant formulation and effectively control the burning characteristic of high energy propellants.

关键词： Phase change material Propellants nanocomposite Thermal decomposition Burning

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An improved deep dilated convolutional neural network for seismic facies interpretation

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Petroleum Science 2024年第3期21卷 1569-1583页

作者： na-Xia Yang Guo-fa Li Ting-Hui Li Dong-Feng Zhao Wei-Wei Gu State Key Laboratory of Petroleum Resources and Engineering CNPC Key Lab of Geophysical ExplorationChina University of Petroleum(Beijing)Beijing 102249China Dagang Branch Research InstituteBGPTianjin300280China

With the successful application and breakthrough of deep learning technology in image segmentation,there has been continuous development in the field of seismic facies interpretation using convolutional neural *** intelligent and automated methods significantly reduce manual labor,particularly in the laborious task of manually labeling seismic ***,the extensive demand for training data imposes limitations on their wider *** overcome this challenge,we adopt the UNet architecture as the foundational network structure for seismic facies classification,which has demonstrated effective segmentation results even with small-sample training ***,we integrate spatial pyramid pooling and dilated convolution modules into the network architecture to enhance the perception of spatial information across a broader *** seismic facies classification test on the public data from the F3 block verifies the superior performance of our proposed improved network structure in delineating seismic facies *** analysis against the traditional UNet model reveals that our method achieves more accurate predictive classification results,as evidenced by various evaluation metrics for image ***,the classification accuracy reaches an impressive 96%.Furthermore,the results of seismic facies classification in the seismic slice dimension provide further confirmation of the superior performance of our proposed method,which accurately defines the range of different seismic *** approach holds significant potential for analyzing geological patterns and extracting valuable depositional information.

关键词： Seismic facies interpretation Dilated convolution Spatial pyramid pooling Internal feature maps Compound loss function

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Model-constrained and data-driven double-supervision acoustic impedance inversion

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Petroleum Science 2023年第5期20卷 2809-2821页

作者： Dong-Feng Zhao na-Xia Yang Jin-Liang Xiong Guo-fa Li Shu-Wen Guo State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249China Dagang Oil Field PetroChinaTianjin300280China Research Institute of Exploration and Development Dagang Oil FieldPetroChinaTianjin300280China

Seismic impedance inversion is an important technique for structure identification and reservoir ***-based and data-driven impedance inversion are the commonly used inversion *** practice,the geophysical inversion problem is essentially an ill-posedness problem,which means that there are many solutions corresponding to the same seismic ***,regularization schemes,which can provide stable and unique inversion results to some extent,have been introduced into the objective function as constrain *** them,given a low-frequency initial impedance model is the most commonly used regularization method,which can provide a smooth and stable ***,this model-based inversion method relies heavily on the initial model and the inversion result is band limited to the effective frequency bandwidth of seismic data,which cannot effectively improve the seismic vertical resolution and is difficult to be applied to complex structural ***,we propose a data-driven approach for high-resolution impedance inversion based on the bidirectional long short-term memory recurrent neural network,which regards seismic data as time-series rather than image-like *** with the model-based inversion method,the data-driven approach provides higher resolution inversion results,which demonstrates the effectiveness of the data-driven method for recovering the high-frequency ***,judging from the inversion results for characterization the spatial distribution of thin-layer sands,the accuracy of high-frequency components is difficult to ***,we add the model constraint to the objective function to overcome the shortages of relying only on the data-driven ***,constructing the supervisor1 based on the bidirectional long short-term memory recurrent neural network,which provides the predicted impedance with higher ***,convolution constraint as supervisor2 is introduced into the objective fu

关键词： Acoustic impedance inversion Model constraints Double supervision BiLSTM neural network Reservoir structure characterization

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Microbiological assessment of indoor air of a teaching hospital in Nigeria

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Asian Pacific Journal of Tropical Biomedicine 2012年第6期2卷 465-468页

作者： Awosika SA Olajubu fa Amusa na Department of Microbiology Olabisi Onabanjo University Department of Medical Microbiology & Parasitology Olabisi Onabanjo University Teaching Hospital Department of Plant Science & Applied Zoology Olabisi Onabanjo University

Objective:To investigate the quality of indoor air of different wards and units of Olabisi Onabanjo University Teaching Hospital, Sagamu, to ascertain their contribution to infection rate in the ***:The microbial quality of indoor air of nine wards/units of Olabisi Onabanjo University Teaching Hospital, Sagamu, Nigeria was conducted. Sedimentation technique using open Petri-dishes containing different culture media was employed and samplings were done twice daily, one in the morning shortly after cleaning and before influx of people/patients into the wards/units and the other in the evening when a lot of activities would have taken place in these wards. Isolates were identified according to standard ***:Results showed that there was a statistically significant difference(氈2= 6.0167) in the bacteria population of the different sampling time whereas it was not so for fungi population(氈2= 0.2857). Male medical ward(MMW) and male surgical general(MSG) recorded the highest bacterial and fungal growth while the operating theatre(OT) was almost free of microbial burden. The bacteria isolates were Staphylococcus aureus, Klebsiellasp., Bacillus cereus, Bacillus subtilis, Streptococcus pyogenes andSerratia marscenceswhile the fungi isolates includedAspergillus flavus, Penicilliumsp.,Fusariumsp.,Candida *** aureuswas the predominantly isolated bacterium whilePenicilliumsp. was the most isolated ***:Though most of the microbial isolates were potential and or opportunistic pathogens, there was no correlation between the isolates in this study and the surveillance report of nosocomial infection during the period of study, hence the contribution of the indoor air cannot be established. From the reduction noticed in the morning samples, stringent measures such as proper disinfection and regular cleaning, restriction of patient relatives' movement in and out of the wards/units need to be enforced so as to imp

关键词： Indoor air OOUTH Open-plate technique Nosocomial infections Staphylococcus aureus Microbiological assessment Microbial quality Bacterial isolate Fungal isolate Opportunistic pathogen Nosocomial infection Infection rate Microbial isolate Penicilliumsp Sedimentation technique

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Three-dimensional hierarchically porous nitrogen-doped carbon from water hyacinth as selenium host for high-performance lithium-selenium batteries

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Rare Metals 2022年第10期41卷 3432-3445页

作者： Wei-na Deng Yan-Hua Li Di-fa Xu Wei Zhou Kai-Xiong Xiang Han Chen Hunan Key of Laboratory of Applied Environmental Photocatalysis Changsha UniversityChangsha410022China School of Metallurgy and Materials Engineering Hunan University of TechnologyZhuzhou412007China

Hierarchically porous nitrogen-doped carbon(HPNC) with interconnected micro-,meso-,and macropores was generated from KOH and urea etching as a carbon scaffold to infuse *** this structure,micropores confine Se as single-chain molecules,preventing the generation of higher-order polyselenides,the mesopores provide effective pathways for electrolyte diffusion and ion transport and offer sufficient void space to accommodate the volume change of Se upon lithiation/delithiation,and the doped nitrogen improves the electrical conductivity of HPNC and increases the utilization of *** applied as a scaffold for Se in a lithium-selenium battery,the Se/HPNC cathode with a large Se content of 67.6 wt% maintains a high discharge capacity of 410 mAh·g^(-1) at the 500 th cycle at1.0 C,and it demonstrates a discharge capacity as high as371 mAh·g^(-1) even at a high current density of 5.0 ***,when the current density returns to 0.2 C,the discharge capacity recovers to 527 mAh·g^(-1) with a capacity retention rate of 90.5% for the first 0.2 C,indicating the excellent structural stability of *** has significant potential for application in energy storage systems.

关键词： Hierarchically porous carbon Nitrogen-doped carbon Li-Se batteries Electrochemical performances

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Radio jets and galaxies as cosmic string probes

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Frontiers of physics 2012年第4期7卷 461-470页

作者： fa-Bo Feng Department of Astronomy Nanjing UniversityNanjing 210093China

The lensing effect of a cosmic string is studied, and some new methods are proposed to detect the cosmic string. The technique for using jets as extended gravitational lensing probes was first explored by Kronberg. We use the ＂alignment-breaking parameter＂ nc as a sensitive indicator of gravitational distortion by a wiggly cosmic string. Then, we applied the non-constant deflection angle to jets, and na of a specific jet is just related to the projected slope of the jet. At least three jets in the sample of Square Kilometer Array （SKA） would have significant signals （na 〉 10°） if the wiggly infinite cosmic string existed. The distortion of elliptical object is also studied and used to do a statistical research on the directions of axes and ellipticities of galaxies. In the direction of the string, we find that galaxies appear to be more elliptical for an observer and the distribution of apparent ellipticity changes correspondingly. The ellipticity distribution of current SDSS spiral sample has the signal- to-noise ratio up to 8.48 which is large enough for astronomical observations. The future survey, such as Large Synoptic Survey Telescope （LSST） and Dark Energy Survey （DES） would weaken the requirement of special geometry in the data processing. As a result, all kinds of distributions, including ellipticity axis distribution, would serve as probes to detect wiggly strings in the near future. In brief, if a wiggly cosmic string existed, these signals would be convenient to be observed with the future weak lensing survey or other surveys in the deep space. If there was no lensing signal in these distributions, it would give the upper limit of the abundance of infinite strings.

关键词： gravitational lensing jets and outflows cosmic string galaxy

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Dissecting the key genomic regions underlying high yield potential in common wheat variety‘Kenong 9204’

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Journal of Integrative Agriculture 2023年第9期22卷 2603-2616页

作者： ZHAO Chun-hua ZHANG na faN Xiao-li JI Jun SHI Xiao-li CUI fa LING Hong-qing LI Jun-ming College of Agriculture Ludong University/Key Laboratory of Molecular Module-based Breeding of High Yield and Abiotic Resistant Plants in Universities of ShandongYantai 264025P.R.China Jiangsu Xuhuai Regional Institute of Agricultural Sciences Xuzhou 221131P.R.China Chengdu Institute of Biology Chinese Academy of SciencesChengdu 610041P.R.China State Key Laboratory of Plant Cell and Chromosome Engineering Institute of Genetics and Developmental BiologyInnovation Academy for Seed DesignChinese Academy of SciencesBeijng 100101P.R.China Center for Agricultural Resources Research Institute of Genetics and Developmental BiologyChinese Academy of SciencesShijiazhuang 050022P.R.China Key Laboratory of Molecular and Cellular Biology Ministry of Education/Hebei Collaboration Innovation Center for Cell Signaling/Hebei Key Laboratory of Molecular and Cellular Biology/College of Life SciencesHebei Normal UniversityShijiazhuang 050024P.R.China

The foundation parents play key roles in the genetic improvement of both yield potential and end-use quality in *** the genetic basis that underlies certain beneficial traits in the foundation parents will provide theoretical reference for molecular breeding by a design approach.‘Kenong 9204’(KN9204)is a candidate foundation parent characterized by ideotype,high yield potential,and particularly high nitrogen fertilizer *** better understand the genetic basis of its high yield potential,high throughput whole-genome re-sequencing(10×)was performed on KN9204,its parental lines and its derivatives.A high-resolution genetic composition map of KN9204 was constructed,which showed the parental origin of the favorable genomic segments based on the identification of excellent yield-related quantitative trait loci(QTL)from a bi-parental mapping *** 693(XY693),a wheat–Thinopyrum ponticum partial amphidiploid,contributed a great deal to the high yield potential of KN9204,and three major stable QTLs from XY693 were fine *** transmissibility of key genomic segments from KN9204 to its derivatives were delineated,indicating that haplotype blocks containing beneficial gene combinations were conserved along with directional selection by *** for selection sweeps in the breeding programs was *** study provides a theoretical reference for the breeding of high-yield wheat varieties by a molecular design approach.

关键词： Kenong 9204 high-yielding potential quantitative trait locus genetic composition map key genomic regions

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Investigating adverse events in long-term care facilities:a systematized review

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Frontiers of Nursing 2023年第4期10卷 399-412页

作者： Dominika Kohanová Martina Lepiešová Daniela Bartoníčková Pavol faťun KatarínaŽiaková Department of Nursing Faculty of Social Sciences and Health CareConstantine the Philosopher University in NitraNitra 94901Slovak Republic Department of Nursing Jessenius Faculty of Medicine in MartinComenius University in BratislavaMartin 03601Slovak Republic Department of Nursing Faculty of Health SciencesPalackýUniversity in OlomoucOlomouc 77515Czech Republic

Objective:This systematized review aimed to synthesize the results of empirical studies focused on the types and factors of adverse events(AEs)that contribute to them in long-term care(LTC)***:The search was conducted in Pro Quest,Scopus,and Pub Med in January 2021 and resulted in 1057 *** content analysis method was used in the data ***:In all,35 studies were identified as relevant for the *** analysis revealed 133 different types of AEs and 60 factors that contributed to ***:In LTC,various AEs occur,most of which are preventable,while many factors that influence their occurrence could be significantly *** an effective analysis of AEs in LTC,it is possible to minimize their occurrence and,at the same time,minimize their negative impact on all par ties concerned.

关键词： adverse event facility factors long-term care healthcare workers

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Effects of interactions between environmental factors and KIF1B genetic variants on the risk of hepatocellular carcinoma in a Chinese cohort

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World Journal of Gastroenterology 2016年第16期22卷 4183-4190页

作者： Jun-Hu Chen Yan-Yan Wang Wei-Biao Lv Yu Gan Wei Chang na-na Tian Xiao-Hui Huang Li Liu Xin-fa Yu Si-Dong Chen Department of Epidemiology School of Public Health and Tropical Medicine Southern Medical University Department of Epidemiology and Biostatistics School of Public Health Guangdong Pharmaceutical University Department of Obstetrics and Gynecology Affiliated Hou Jie Hospital of Guangdong Medical College Department of Oncology The First People’s Hospital of Shunde

Aim: To examine the effect of the potential interaction between KIF1 B variants(rs17401966 and rs3748578) and environmental factors on the risk of hepatocellular carcinoma(HCC) in a high-risk region in ***: Three hundred and six patients with HCC and 306 hospital-based control participants residing in the Shunde region of Guangdong Province, China were enrolled. Clinical characteristics were collected by reviewing the complete medical histories from the patient archives, and epidemiological data were collected using a questionnaire and clinical examination. Two single nucleotide polymorphisms(SNPs) of KIF1B(rs17401966 and rs3748578) were chosen for the current study. All subjects were genotypedusing a Taq Man real-time polymerase chain reaction. Multiplicative and additive logistic regression models were used to evaluate various gene-environment ***: Smoking, frequent consumption of raw freshwater fish, hepatitis B virus(HBV) infection, and a family history of HCC were important risk factors for HCC in this population. Chronic infection with HBV was the most important environmental risk factor for HCC [odds ratio(OR) = 12.02; 95% confidence interval(95%CI): 6.02-24.00]. No significant association was found between the KIF1 B variants alone and the risk of HCC. Nevertheless, a significant additive effect modification was observed between rs17401966 and alcohol consumption(P for additive interaction = 0.0382). Compared with non-drinkers carrying either the AG or GG genotype of rs17401966, individuals classified as alcohol consumers with the AA genotype of rs17401966 had a significantly increased risk of HCC(OR = 2.36; 95%CI: 1.49-3.74).CONCLUSION: The gene-environment interaction between the KIF1 B rs17401966 variant and alcohol consumption may contribute to the development of HCC in Chinese individuals.

关键词： Hepatocellular carcinoma Kinesin family member 1B Environmental factors Alcohol drinking Gene-environment interaction

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Design,Synthesis and Biological Evaluation of Bengamide Analogues as ClpP Activators

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Chinese Journal of Chemistry 2020年第10期38卷 1111-1115页

作者： Xue-Qing Kong Bing-Yan Wei Chen-Xi Yu Xiang na Guan Wei-Ping Ma Gang Liu Cai-Guang Yang fa-Jun nan Chinese national Center for Drug Screening CAS Key Laboratory of Receptor ResearchStote Key Laboratory of Drug ResearchShanghai Institute of Materia MedicaChinese Academy of Sciences555 Zuchongzhi RoadShanghai 201203China University of Chinese Academy of Sciences No.19A Yuquan RoadBeijing 100049China Yantai Key Laboratory of nanomedicine&Advanced Preparations Yantai Institute of Materia MedicaNo.39Science and Technology AvenueHigh-tech Industrial Development ZoneYantaiShandong 264000China

Summary of main observation and conclusion To combat multidrug-resistant Gram-positive bacteria,new antimicrobials particularly those with novel mechanism of action are badly *** with conventional antibiotics which are typical inhibitors,small-molecule activators of bacterial CIpP represent a new class of *** ClpP activator has been developed for clinical ***,we conducted a screening on our library of benga-mide-like ring opened analogues and found that L472-2 possesses a low minimum inhibitory concentration(MIC)against *** and shows no activity for ClpP activation in vitro,but it displayed reduced antibacterial activity against *** with clpP *** order to obtain bengamide analogues that activate ClpP in vitro as well as possess antibacterial activity,we perform further structural modifications starting from *** 37 re-mains the antimicrobial activity and activation of ClpP protein in vitro,which could be viewed as a new chemical scaffold for ClpP activators and worthy of further investigation.

关键词： analogues activation starting

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