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Literature Analysis on Fluorescence in situ Hybridization in China during 2002-2016 被引量:1
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作者 Mecao ZHUO Guanghuan YANG +2 位作者 Menghan LI Yan HE Ba DAN 《Asian Agricultural Research》 2017年第12期64-67,共4页
In order to explore researches about the chromosome karyotype analysis and fluorescence in situ hybridization(FISH) technology in China,using the bibliometric method,taking " fluorescence in situ hybridization(FI... In order to explore researches about the chromosome karyotype analysis and fluorescence in situ hybridization(FISH) technology in China,using the bibliometric method,taking " fluorescence in situ hybridization(FISH) " and " chromosome" as key words,this paper made a statistical analysis on the literature published in China National Knowledge Infrastructure(CNKI) during 2002-2016.The results indicated that the number of papers published in 2002 was the smallest(37),while the number of papers published in 2012 was the largest(125).In terms of the distribution of organizations of authors,in 1201 papers,11 organizations published papers ≥15,accounting for 21.65%.In terms of distribution of papers published by different periodicals,11 periodicals published papers ≥10,accounting for 17.65%.In terms of the papers supported by foundation projects,in all papers searched,377 papers were supported by foundation projects,accounting for 31.39%.In terms of the distribution of doctoral and master's dissertations,259 papers were master's dissertations,accounting for 21.57%;92 papers were doctoral dissertations,accounting for 7.66%. 展开更多
关键词 Fluorescence in situ hybridization(FISH) technology CHROMOSOME BIBLIOMETRIC Literature analysis
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DDM regression analysis of the in-situ stress field in a non-linear fault zone 被引量:9
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作者 Ke Li Ying-yi Wang Xing-chun Huang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2012年第7期567-573,共7页
A multivariable regression analysis of the in-situ stress field, which considers the non-linear deformation behavior of faults in practical projects, is presented based on a newly developed three-dimensional displacem... A multivariable regression analysis of the in-situ stress field, which considers the non-linear deformation behavior of faults in practical projects, is presented based on a newly developed three-dimensional displacement discontinuity method (DDM) program. The Bar- ton-Bandis model and the Kulhaway model are adopted as the normal and the tangential deformation model of faults, respectively, where the Mohr-Coulomb failure criterion is satisfied. In practical projects, the values of the mechanical parameters of rock and faults are restricted in a bounded range for in-situ test, and the optimal mechanical parameters are obtained from this range by a loop. Comparing with the traditional finite element method (FEM), the DDM regression results are more accurate. 展开更多
关键词 displacement discontinuity method (DDM) in-situ stress regression analysis FAULTS ROCK
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Dry eye and corneal sensitivity after small incision lenticule extraction and femtosecond laser-assisted in situ keratomileusis:a Meta-analysis 被引量:9
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作者 Wen-Ting Cai Qing-Yu Liu +6 位作者 Cheng-Da Ren Qing-Quan Wei Jun-Ling Liu Qian-Yi Wang Ya-Ru Du Meng-Mei He Jing Yu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2017年第4期632-638,共7页
AIM:To assess the corneal sensitivity and the incidences of dry eye after small incision lenticule extraction(SMILE) and femtosecond laser-assisted in situ keratomileusis(FSLASIK).METHODS:The Meta-analysis was p... AIM:To assess the corneal sensitivity and the incidences of dry eye after small incision lenticule extraction(SMILE) and femtosecond laser-assisted in situ keratomileusis(FSLASIK).METHODS:The Meta-analysis was performed using Rev Man 5.3.We searched on Pub Med from inception to March 2016.Summary weighted mean difference(WMD) and 95% confidence intervals(CIs) were used to analyze the datum.Random-effects or fixed-effects models were chosen up to between-study heterogeneity.The main outcomes were composed of the Ocular Surface Disease Index(OSDI) scores,tear film break-up time(TBUT),Schirmer Test and corneal sensitivity.RESULTS:Eight eligible studies including 772 eyes(386 in SMILE group and 386 in FS-LASIK group) were identified.The parameters have no significiant difference heterogeneity between SMILE and FS-LASIK group preoperatively.There were significant differences between the two groups in OSDI scores at one and three months postoperatively,in TBUT at one and three months postoperatively,in corneal sensitivity at one week,about one month and three months postoperatively.However,there was no significant difference observed in Schirmer Test at the follow-up periods.CONCLUSION:Compare to FS-LASIK,dry eye and the corneal sensitivity recover better in the SMILE group,in first three months after the surgery. 展开更多
关键词 dry eye corneal sensation small incision lenticule extraction femtosecond laser-assisted in situ keratomileusis META-analysis
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Data processing and preliminary results of the Chang'e-3 VIS/NIR Imaging Spectrometer in-situ analysis 被引量:3
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作者 Bin Liu Chun-Lai Li +7 位作者 Guang-Liang Zhang Rui Xu Jian-Jun Liu Xin Ren Xu Tan Xiao-Xia Zhang Wei Zuo Wei-Bin Wen 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2014年第12期1578-1594,共17页
The Chang'e-3 Visible and Near-infrared Imaging Spectrometer (VNIS) is one of the four payloads on the Yutu rover. After traversing the landing site during the first two lunar days, four different areas are detecte... The Chang'e-3 Visible and Near-infrared Imaging Spectrometer (VNIS) is one of the four payloads on the Yutu rover. After traversing the landing site during the first two lunar days, four different areas are detected, and Level 2A and 2B ra- diance data have been released to the scientific community. The released data have been processed by dark current subtraction, correction for the effect of temperature, radiometric calibration and geometric calibration. We emphasize approaches for re- flectance analysis and mineral identification for in-situ analysis with VNIS. Then the preliminary spectral and mineralogical results from the landing site are derived. After comparing spectral data from VNIS with data collected by the Ma instrument and samples of mare that were returned from the Apollo program, all the reflectance data have been found to have similar absorption features near 1000 nm except lunar sample 71061. In addition, there is also a weak absorption feature between 1750-2400nm on VNIS, but the slopes of VNIS and Ma reflectance at longer wavelengths are lower than data taken from samples of lunar mare. Spectral parameters such as Band Centers and Integrated Band Depth Ratios are used to analyze mineralogical features. The results show that detection points E and N205 are mixtures of high-Ca pyroxene and olivine, and the composition of olivineat point N205 is higher than that at point E, but the compositions of detection points S3 and N203 are mainly olivine-rich. Since there are no obvious absorption features near 1250 nm, plagioclase is not directly identified at the landing site. 展开更多
关键词 Chang'e-3 -- VNIS -- in-situ analysis -- data processing
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A Data Analysis Framework for Earth System Simulation within an <i>In-Situ</i>Infrastructure
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作者 D. Wang X. Luo +1 位作者 F. Yuan N. Podhorszki 《Journal of Computer and Communications》 2017年第14期76-85,共10页
This paper presents a generic procedure to implement a scalable and high performance data analysis framework for large-scale scientific simulation within an in-situ infrastructure. It demonstrates a unique capability ... This paper presents a generic procedure to implement a scalable and high performance data analysis framework for large-scale scientific simulation within an in-situ infrastructure. It demonstrates a unique capability for global Earth system simulations using advanced computing technologies (i.e., automated code analysis and instrumentation), in-situ infrastructure (i.e., ADIOS) and big data analysis engines (i.e., SciKit-learn). This paper also includes a useful case that analyzes a globe Earth System simulations with the integration of scalable in-situ infrastructure and advanced data processing package. The in-situ data analysis framework can provides new insights on scientific discoveries in multiscale modeling paradigms. 展开更多
关键词 IN-situ DATA analysis Source Code analysis DATA STAGING ADIOS Earth System Model Machine Learning SciKit-Learn E3SM
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Sugar Cane (Saccharum officinarum L.) Analysis through Biospeckle and Spectroscopy (NIR) 被引量:2
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作者 Matheus Sevillano Marcondes Keylla Guiguer Silva +2 位作者 Armando Kazuo Fujii Ronei Jesus Poppi Juliana Aparecida Fracarolli 《Journal of Agricultural Science and Technology(B)》 2017年第1期62-68,共7页
The objective of this paper was to evaluate the sugar and water content in sugar cane samples by means of twonon-destructive techniques in comparison with conventional methods. One non-destructive technique is the Bio... The objective of this paper was to evaluate the sugar and water content in sugar cane samples by means of twonon-destructive techniques in comparison with conventional methods. One non-destructive technique is the Biospeckle, aninteraction between the laser and the biological material which provides information about the material. The other technique is thenear infrared spectroscopy (NIR). The Biospeckle technique has been constantly used in agricultural engineering. In this paper, therelation between the water and the sugar contents were obtained. The results for the Biospeckle were acquired through the moment ofinertia (MI). The data acquired through already consolidated methodologies were used to quantify the samples' water and sugarcontents, correlating to the spectroscopy results and also to the Biospeckle. It was obtained a high determination coefficient (R^2 =0.9287) between the predicted Brix by the model generated by NIR spectroscopy and Brix measured by refractometer. It was alsopossible to differentiate the water contents of the sugar cane samples both externally lit (husk) and internally lit (cut) by Biospeckleanalysis through the calculation of MI. It is possible to evaluate the water content and the sugar content in samples combiningBiospeckle and NIR spectroscopy, which are non-invasive and non-destructive methods. 展开更多
关键词 SUGAR content water content non-destructive analysis dynamic speckle image processing laser.
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Analysis of sp Pillar Stability Experiment: Continuous thermo-mechanical model development and calibration 被引量:1
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作者 R. Blaheta P. Byczanski +5 位作者 M. ermák R. Hrtus R. Kohut A. Kolcun J. Malík S. Sysala 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2013年第2期124-135,共12页
The paper describes an analysis of thermo-mechanical (TM) processes appearing during the Aspo Pillar Stability Experiment (APSE). This analysis is based on finite elements with elasticity, plasticity and dam- age ... The paper describes an analysis of thermo-mechanical (TM) processes appearing during the Aspo Pillar Stability Experiment (APSE). This analysis is based on finite elements with elasticity, plasticity and dam- age mechanics models of rock behaviour and some least squares calibration techniques. The main aim is to examine the capability of continuous mechanics models to predict brittle damage behaviour of gran- ite rocks. The performed simulations use an in-house finite element software GEM and self-developed experimental continuum damage MATLAB code. The main contributions are twofold. First, it is an inverse analysis, which is used for (1) verification of an initial stress measurement by back analysis of conver- gence measurement during construction of the access tunnel and (2) identification of heat transfer rock mass properties by an inverse method based on the known heat sources and temperature measurements. Second, three different hierarchically built models are used to estimate the pillar damage zones, i.e. elas- tic model with Drucker-Prager strength criterion, elasto-plastic model with the same yield limit and a combination of elasto-plasticity with continuum damage mechanics. The damage mechanics model is also used to simulate uniaxial and triaxial compressive strength tests on the ,Aspo granite. 展开更多
关键词 In situ pillar stability experiment Continuous mechanics Damage of granite rocks Model calibration by back analysis Finite element method (FEM)
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Clinical outcomes of small incision lenticule extraction versus femtosecond laser-assisted LASIK for myopia: a Meta-analysis 被引量:12
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作者 Huan Yan Li-Yan Gong +1 位作者 Wei Huang Yan-Li Peng 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2017年第9期1436-1445,共10页
AIM:To evaluate the possible differences in visual quality between small incision lenticule extraction(SMILE)and femtosecond laser in situ keratomileusis(FS-LASIK)for myopia.METHODS:A Meta-analysis was performed... AIM:To evaluate the possible differences in visual quality between small incision lenticule extraction(SMILE)and femtosecond laser in situ keratomileusis(FS-LASIK)for myopia.METHODS:A Meta-analysis was performed.Patients were from previously reported comparative studies treated with SMILE versus FS-LASIK.The Pub Med,EMBASE,Cochrane,Web of Science and Chinese databases(i.e.WANFANG and CNKI)were searched in Nov.of 2016 using Rev Man 5.1 version software.The differences in visual acuity,aberration and biomechanical effects within six months postoperatively were showed.Twenty-seven studies including 4223 eyes were included.RESULTS:No significant differences were observed between SMILE and FS-LASIK in terms of the proportion of eyes that lost one or more lines of corrected distance visual acuity after surgery(P=0.14),the proportion of eyes achieving an uncorrected distance visual acuity of 20/20or better(P=0.43),the final refractive spherical equivalent(P=0.89),the refractive spherical equivalent within±1.00diopter of the target values(P=0.80),vertical coma(P=0.45)and horizontal coma(P=0.06).Compared with the FSLASIK group,total higher-order aberration(P〈0.001)and spherical aberration(P〈0.001)were higher and the decrease in corneal hysteresis(P=0.0005)and corneal resistance factor(P=0.02)were lower in the SMILE group.CONCLUSION:SMILE and FS-LASIK are comparable in efficacy,safety and predictability for correcting myopia.However,the aberration in the SMILE group is superior to that in the FS-LASIK group,and the loss of biomechanical effects may occur less frequently after SMILE than after FS-LASIK. 展开更多
关键词 META-analysis small incision lenticuleextraction femtosecond laser in situ keratomileusis MYOPIA
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A Novel Dinuclear Copper(Ⅱ)Complex:Synthesis,Crystal Structure,Properties and Hirshfeld Surface Analysis 被引量:2
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作者 张冲 杨莉 +1 位作者 陈浩 张淑华 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第11期1904-1911,共8页
A novel copper complex [Cu2(L)(DMF)2](1, H4L =(1 Z,N?Z)-3,5-dibromo-N?-((3,5-dibromo-2-hydroxyphenyl)(hydroxy)methylene)-2-hydroxybenzohydrazonic acid which was synthesized by in-situ oxidation reaction... A novel copper complex [Cu2(L)(DMF)2](1, H4L =(1 Z,N?Z)-3,5-dibromo-N?-((3,5-dibromo-2-hydroxyphenyl)(hydroxy)methylene)-2-hydroxybenzohydrazonic acid which was synthesized by in-situ oxidation reaction derived from H2hdb(H2hdb = 6,6′-((1 E,1?E)-hydrazine-1,2-diylidenebis(methanylylidene)) bis(2,4-dibromophenol)) has been synthesized and characterized by IR, elemental analysis(CHN), TG and single-crystal X-ray diffraction. The single crystal belongs to monoclinic system, space group P21/c with a = 13.538(1), b = 3.912(1), c = 23.778(1)A°, β = 105.232(5)o, Mr = 857.08, V = 1214.9(1) A°^3, Z = 2, Dc = 2.343 g/cm^3, F(000) = 824, μ = 8.375 mm^–1, R = 0.0566, and w R = 0.1610. Compound 1 displays weak anti-ferromagnetic interactions through a η^1:η^1:η^1:η^1:η^1:η^1:μ2-L^4- bridging mode. Hirshfeld surface analysis revealed that complex 1 was supported mainly by Br···H and H···H intermolecular interactions. 展开更多
关键词 N O-Schiff-base ligand in-situ oxidation reaction magnetic properties Hirshfeld surfaces analysis
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Diagnosing Battery Degradation via Gas Analysis
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作者 Michael Metzger Hubert A.Gasteiger 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2022年第3期688-692,共5页
Interfacial reactions in lithium-ion batteries often involve gaseous reaction products.Mechanistic investigation of material degradation processes requires a technique to identify and quantify these gases in battery c... Interfacial reactions in lithium-ion batteries often involve gaseous reaction products.Mechanistic investigation of material degradation processes requires a technique to identify and quantify these gases in battery cells.Online electrochemical mass spectrometry(OEMS)is an operando gas analysis method that continuously samples the headspace of a custom battery cell.Real-time gas analysis by quantitative OEMS was used to create mechanistic understanding of battery degradation reactions,some of which will be highlight in this article. 展开更多
关键词 aging mechanisms BATTERIES energy storage gas analysis in situ and operando characterization
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Applied research of correspondence analysis method in waste tailings reservoir heavy metal pollution monitoring points optimization
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作者 WANG Cong-lu WU Chao +1 位作者 LI Zi-jun XUE Sheng-guo 《Journal of Coal Science & Engineering(China)》 2010年第4期419-423,共5页
In order to optimize monitoring points and monitoring factor, the relationshipbetween pollutants and soil sample were established by correspondence analysis.Thestudy results show that the reflecting monitoring points ... In order to optimize monitoring points and monitoring factor, the relationshipbetween pollutants and soil sample were established by correspondence analysis.Thestudy results show that the reflecting monitoring points and monitoring factors in thegraphic on the same factor axis can clearly express the intrinsic link between pollutantsand monitoring points and distribution characteristics.To determine the main monitoringpoint and the main monitoring indicators can reduce and optimize the number of monitoringpoints under the premise of ensuring the typical and representative of monitoring data.Using the correlation of pollutants can reduce the number of monitoring indicators and improvethe effectiveness of data collection. 展开更多
关键词 测点优化 对应分析 重金属污染 尾矿库废水 污染物分布 应用 监测因子 监测指标
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Predictive analysis of stress regime and possible squeezing deformation for super-long water conveyance tunnels in Pakistan
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作者 Wang Chenghu Bao Linhai 《International Journal of Mining Science and Technology》 SCIE EI 2014年第6期825-831,共7页
The prediction of the stress field of deep-buried tunnels is a fundamental problem for scientists and engineers. In this study, the authors put forward a systematic solution for this problem. Databases from the World ... The prediction of the stress field of deep-buried tunnels is a fundamental problem for scientists and engineers. In this study, the authors put forward a systematic solution for this problem. Databases from the World Stress Map and the Crustal Stress of China, and previous research findings can offer prediction of stress orientations in an engineering area. At the same time, the Andersonian theory can be used to analyze the possible stress orientation of a region. With limited in-situ stress measurements, the Hoek–Brown Criterion can be used to estimate the strength of rock mass in an area of interest by utilizing the geotechnical investigation data, and the modified Sheorey's model can subsequently be employed to predict the areas' stress profile, without stress data, by taking the existing in-situ stress measurements as input parameters. In this paper, a case study was used to demonstrate the application of this systematic solution. The planned Kohala hydropower plant is located on the western edge of Qinghai–Tibet Plateau.Three hydro-fracturing stress measurement campaigns indicated that the stress state of the area is SH>-Sh> SVor SH> SV> Sh. The measured orientation of SHis NEE(N70.3°–89°E), and the regional orientation of SHfrom WSM is NE, which implies that the stress orientation of shallow crust may be affected by landforms. The modified Sheorey model was utilized to predict the stress profile along the water sewage tunnel for the plant. Prediction results show that the maximum and minimum horizontal principal stresses of the points with the greatest burial depth were up to 56.70 and 40.14 MPa, respectively, and the stresses of areas with a burial depth of greater than 500 m were higher. Based on the predicted stress data, large deformations of the rock mass surrounding water conveyance tunnels were analyzed. Results showed that the large deformations will occur when the burial depth exceeds 300 m. When the burial depth is beyond 800 m, serious squeezing deformations will occur in the surrounding rock masses, thus requiring more attention in the design and construction. Based on the application efficiency in this case study, this prediction method proposed in this paper functions accurately. 展开更多
关键词 预测分析 应力状态 输水隧道 挤压变形 巴基斯坦 地应力测量 埋藏深度 地壳应力
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Clonal Analysis of Peripheral Papilloma and Cancerous Cells of the Breast
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作者 Qi Yu Yun Niu +2 位作者 Yong Yu Xiumin Ding Yurong Shi 《Chinese Journal of Clinical Oncology》 CSCD 2007年第6期401-404,共4页
OBJECTIVE Because almost al malignancies represent monoclonal proliferations,we have studied the clonal status of peripheral papil omas (peri-PM),ductal carcinomas in situ(DCIS),and normal breast tissues to explore a ... OBJECTIVE Because almost al malignancies represent monoclonal proliferations,we have studied the clonal status of peripheral papil omas (peri-PM),ductal carcinomas in situ(DCIS),and normal breast tissues to explore a reliable way to distinguish benign and malignant(or pre-malignant) cases previously diagnosed morphologically. METHODS Twenty-six cases of peri-PM,25 cases of peri-PM with atypical ductal hyperplasia(ADH),27 cases of DCIS,16 cases of developed canceration and 20 specimens of normal tissue were examined in the study.The clonal status of these tissues was studied using an assay based on inactivation mosaicism of the lenth-polymorphic X-chromosomes at the androgen receptor(AR)locus. RESULTS Loss of polymorphism at the AR locus was found in all DCIS cases and 10 cases(10/25,40.0%)of peri-PM with ADH,indicating the monoclonality of the tumors.Twenty-four out of 26(92.3%)cases with peri-PM and 19 specimens of normal tissue were shown to be polyclonal.In 16 cases of developed canceration,identical X chromosome inactivation(monoclonal alterations)was observed from both the peri-PM with ADH part,and the DCIS part in each case. CONCLUSION These results contribute to the understanding of the genetic changes of peri-PM,and confirm the peri-PM withADH as a precancerous lesion of the breast.Clonal analysis might be a useful modality to screen high-risk cases from precancerous lesions or to distinguish between benign hyperplasia and early carcinoma. 展开更多
关键词 乳房癌 治疗 临床表现 病理学
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基于岩心分析的稠油火驱过程中组分转化路径
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作者 孙新革 杨凤祥 +3 位作者 李海波 展宏洋 高成国 袁士宝 《特种油气藏》 CAS CSCD 北大核心 2024年第3期85-90,共6页
针对火驱现场原油组分转化不明确的问题,以新疆油田红浅1井区稠油油藏为例,运用红外光谱和GC-MS方法,结合岩心分析结果与稠油反应机理,认为稠油组分反应变化分为烃类分子氧化、稠油组分化学键断裂和芳环自由基缩合生焦变化。将研究成果... 针对火驱现场原油组分转化不明确的问题,以新疆油田红浅1井区稠油油藏为例,运用红外光谱和GC-MS方法,结合岩心分析结果与稠油反应机理,认为稠油组分反应变化分为烃类分子氧化、稠油组分化学键断裂和芳环自由基缩合生焦变化。将研究成果应用于稠油组分转化路径的分析,结果表明:低温阶段,稠油组分反应最集中,以缩聚和热裂解反应为主;燃烧阶段,芳环自由基聚合生焦,C-H键断裂加氧形成OH、CHO、CO等官能团;高温氧化阶段,为焦炭和重质组分(胶质、沥青质)的燃烧。研究内容验证了火驱过程中焦炭燃烧使稠油升温降黏、稠油组分转化为焦炭启动燃烧的结论,加深认识火驱过程中燃料形成和转化的意义。 展开更多
关键词 火驱 稠油 氧化反应 热反应 转化路径 岩心分析
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近废型稠油油藏火驱效益开发新思路
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作者 郑懿琼 张涛 +2 位作者 刘海英 阮聪慧 邹帅 《油气藏评价与开发》 CSCD 北大核心 2024年第3期504-509,518,共7页
近废型稠油油藏难以通过常规开发方式有效动用剩余储量,火驱技术为此类油藏进一步提高采收率提供方向。现阶段,火驱技术已趋于成熟,但由于成本投入大、经济性差,火驱技术的推广应用面临困境。通过引入量本利分析法中的盈亏平衡模型和敏... 近废型稠油油藏难以通过常规开发方式有效动用剩余储量,火驱技术为此类油藏进一步提高采收率提供方向。现阶段,火驱技术已趋于成熟,但由于成本投入大、经济性差,火驱技术的推广应用面临困境。通过引入量本利分析法中的盈亏平衡模型和敏感性分析,从多维度的经营视角,揭示不同油价年产油量和成本的平衡关系,明确影响火驱经济性的关键指标,进而推动生产运行优化和决策效能提升。研究结果表明,由于储层前后认识差距大,投入力度大于产出力度,同时管控方向不明确,导致火驱成本有效性低,持续开发经营风险认识不足,影响油藏开发投入决策。研究结果为火驱的经营效益提升指明方向,也为近废型稠油油藏效益开发提供管理新思路。 展开更多
关键词 近废型稠油油藏 火驱技术 效益提升 量本利分析法 决策优化
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884例性染色体异常胎儿产前诊断结果分析
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作者 杨微微 姚立英 +4 位作者 任晨春 王文靖 张海霞 李雯 李博 《检验医学》 CAS 2024年第2期149-154,共6页
目的 对884例无创产前筛查(NIPS)提示性染色体异常的羊水样本进行核型分析、荧光原位杂交技术(FISH)和拷贝数变异测序(CNV-seq)检测,探讨不同方法在产前诊断中的价值。方法 选取2015年1月—2022年12月天津市中心妇产科医院孕早期NIPS提... 目的 对884例无创产前筛查(NIPS)提示性染色体异常的羊水样本进行核型分析、荧光原位杂交技术(FISH)和拷贝数变异测序(CNV-seq)检测,探讨不同方法在产前诊断中的价值。方法 选取2015年1月—2022年12月天津市中心妇产科医院孕早期NIPS提示胎儿为性染色体异常的孕妇884例,于孕中期采集羊水样本,进行羊水细胞核型分析和FISH检测,对结果不一致或培养失败的样本进一步行CNV-seq检测。结果 884例孕妇中,有341例(38.6%)检出异常核型,11例(1.2%)羊水细胞培养失败。NIPS性染色体阳性预测值为39.2%(341/873)。341例核型分析异常样本中,最常见的核型异常类型是47,XXY(108例),其次为47,XXX(80例)、47,XYY(68例)、45,X(18例),共检出51例嵌合体。884例孕妇中,有862例FISH检测结果与核型分析或CNV-seq结果一致,FISH的阳性预测值为97.5%;24例与核型分析结果不一致,进一步行CNV-seq检测,有22例CNV-seq结果与核型分析结果一致,并能相互补充分析;2例不一致样本中,1例核型分析结果为46,~+mar,FISH和CNV-seq结果均为45,X;1例核型分析结果为嵌合Y染色体异染色质区缺失,FISH和CNV-seq结果均为嵌合体,结构未见异常。结论 NIPS提示性染色体异常时,建议首选FISH和核型分析联合检测,可快速、准确地诊断染色体异常。对于疑似染色体特殊结构异常,建议进行FISH、核型分析和CNV-seq联合检测,可明确遗传学病因。 展开更多
关键词 无创产前筛查 染色体核型分析 荧光原位杂交技术 拷贝数变异测序 性染色体异常 产前诊断
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核型分析联合其他遗传学检测技术在高龄孕妇产前诊断中的应用
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作者 马丽爽 霍平 +3 位作者 楚伟 杜润璇 王向静 高健 《河北医药》 CAS 2024年第10期1483-1486,1491,共5页
目的探讨核型分析联合单核苷酸多态性微阵列技术(single nucleotide polymorphism array,SNP array)或荧光原位杂交技术(fluorescence in situ hybridization,FISH)或细菌人工染色体微珠标记技术(BACs on Beads,BoBs)在高龄孕妇产前诊... 目的探讨核型分析联合单核苷酸多态性微阵列技术(single nucleotide polymorphism array,SNP array)或荧光原位杂交技术(fluorescence in situ hybridization,FISH)或细菌人工染色体微珠标记技术(BACs on Beads,BoBs)在高龄孕妇产前诊断中的应用价值。方法回顾性研究因高龄行产前诊断的930例孕妇,全部行核型分析,联合BoBs检测420例,联合SNP array检测343例,联合FISH检测167例,分析其染色体结果及妊娠结局。结果930例胎儿中,核型异常192例(20.7%),三体综合征中以21-三体居多,性染色体异常中以克氏征居多。在核型联合其他检测中,联合SNP array检测可显著提高胎儿染色体异常检出率,差异有统计学意义(χ^(2)=6.191,P=0.013)。对于染色体嵌合体的诊断,核型联合FISH检测可更精准地确定嵌合类型及比例。孤立性高龄胎儿染色体异常风险相对较低,高龄合并无创高危胎儿染色体异常率最高,在高龄合并超声软指标中,随超声软指标数目增多,染色体异常率随之升高(P=0.001)。高龄孕妇年龄与核型异常、非整倍体尤其21三体的发生率呈正相关(P<0.05)。结论孤立性高龄孕妇胎儿染色体异常风险相对较低,高龄合并无创高危胎儿染色体异常的风险高,随超声软指标数目增多、孕妇年龄增长胎儿染色体异常的风险增加,核型联合FISH检测可更精准地确定嵌合类型及比例,核型分析联合其他检测尤其与SNP array技术可显著提高染色体异常检出率,有利于遗传咨询及再生育指导,是高龄孕妇首选的产前诊断方案。 展开更多
关键词 高龄孕妇 核型分析 SNP array技术 BoBs技术 FISH技术
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大吨位箱梁曲线段梁上运梁承压箱梁受力分析
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作者 王建强 朱广杰 +1 位作者 王飞 赵卓 《铁道工程学报》 EI CSCD 北大核心 2024年第3期45-51,共7页
研究目的:杭甬高速复线宁波段一期工程S1标段采用大吨位预应力混凝土箱梁(50 m/1650 t),使用YL1800型运梁车采用单车跨双幅梁上运梁方案,为研究大吨位箱梁在小半径曲线段(R=1800 m)进行梁上运梁时下部承压箱梁的受力性能,验证运梁方案... 研究目的:杭甬高速复线宁波段一期工程S1标段采用大吨位预应力混凝土箱梁(50 m/1650 t),使用YL1800型运梁车采用单车跨双幅梁上运梁方案,为研究大吨位箱梁在小半径曲线段(R=1800 m)进行梁上运梁时下部承压箱梁的受力性能,验证运梁方案的可行性,对下部承压箱梁进行了测试与分析。研究结论:(1)大吨位箱梁在梁上运梁过程中,承压箱梁跨中截面顶板、底板沿纵向均处于受压状态,顶板沿横向处于受压状态,箱梁的受力满足规范要求;(2)随着运梁车偏载距离的增大,承压箱梁的应力和跨中挠度逐渐增大,运梁车向低侧偏载时对箱梁应力和跨中挠度影响较大,建议在梁上运梁时运梁车向高低两侧偏载不应超过1000 mm;(3)本研究成果可为大吨位箱梁梁上运梁施工提供参考。 展开更多
关键词 大吨位箱梁 梁上运梁 小半径曲线段 现场测试 有限元分析
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多腔室秸秆原位炭化还田设备设计
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作者 姚宗路 张帅帅 +5 位作者 贾吉秀 霍丽丽 李粤 朱本海 李媛 赵立欣 《农业工程学报》 EI CAS CSCD 北大核心 2024年第11期212-219,共8页
原位炭化还田技术可将田间秸秆就地直接转化为生物炭,改善土壤结构,解决秸秆直接还田腐解慢、出苗率低、病虫害严重等问题。但目前炭化还田设备仍存在炭化不均匀,运行稳定性差,生产效率低等问题。该研究基于精准控氧控温炭化要求,在前... 原位炭化还田技术可将田间秸秆就地直接转化为生物炭,改善土壤结构,解决秸秆直接还田腐解慢、出苗率低、病虫害严重等问题。但目前炭化还田设备仍存在炭化不均匀,运行稳定性差,生产效率低等问题。该研究基于精准控氧控温炭化要求,在前期样机基础上,创新研发了立式多腔限域式炭化反应器,研制强化物料定向流动的多翅片型扰动部件,并运用ANSYS Workbench进行仿真模拟和结构优化,研制热解气清洁燃烧及高温烟气换热回用系统,集成秸秆捡拾粉碎系统及田间作业机具,研制立式多腔室秸秆原位炭化还田设备。以玉米秸秆为原料进行炭化试验,设备秸秆处理量为500 kg/h,生物炭产率为125 kg/h,固定碳含量为50.30%,系统能量利用率为70.66%,产出的炭达到Ⅰ级生物炭还田标准,燃烧烟气中颗粒物、NO_(x)、SO_(x)等排放均满足国标要求,整机系统运行稳定,满足设计标准,为秸秆直接炭化还田提供了技术及装备支撑。 展开更多
关键词 秸秆 热解原位炭化 生物炭还田 设备 能量分析
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江西会昌锡坑迳斑岩型锡矿床成矿系统发育特征与找矿模型
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作者 邓迪 赵正 +2 位作者 刘善宝 李超 李陈浩 《矿床地质》 CAS CSCD 北大核心 2024年第1期144-158,共15页
锡坑迳矿田位于南岭成矿带东段与武夷山成矿带交会部位,以早白垩世连续的岩浆喷发-侵入活动与多类型锡多金属成矿作用为特色。矿田内围绕似斑状花岗岩和花岗斑岩发育了岩背斑岩型、淘锡坝和矿背隐爆层间裂隙带型、苦竹岽和凤凰岽云英岩... 锡坑迳矿田位于南岭成矿带东段与武夷山成矿带交会部位,以早白垩世连续的岩浆喷发-侵入活动与多类型锡多金属成矿作用为特色。矿田内围绕似斑状花岗岩和花岗斑岩发育了岩背斑岩型、淘锡坝和矿背隐爆层间裂隙带型、苦竹岽和凤凰岽云英岩-破碎带蚀变岩型等大中型锡矿床。这些矿床的矿化-蚀变特征可与玻利维亚锡矿带、银岩、维拉斯托和洋滨等国内外斑岩型锡矿床类比,又独具特色,是研究斑岩型锡成矿系统发育特征与找矿模型的理想区域。文章在详细的野外地质调查基础上,系统总结了锡坑迳矿田内各类锡多金属矿化组合特征和蚀变结构,并对岩背矿床和淘锡坝矿床锡石开展了电子探针和LA-ICP-MS原位微区分析。研究结果显示,所有锡石样品均具有La、Pr、Gd和Tb的正异常、Ce与Eu的负异常、明显的Zr/Hf分馏和不规则的稀土元素配分模式,指示成矿热液早期阶段及锡石沉淀阶段经历了流体不相容。岩背锡石较淘锡坝锡石具有高的Ti/Zr和Ti/Sc比值,指示其更为靠近矿化中心。笔者研究认为,锡坑迳斑岩型锡成矿系统矿化类型包括细脉状、浸染状和细网脉状,围岩蚀变由早到晚、由成矿中心向外依次发育黄玉石英带、绿泥石-黄玉石英岩化带、绿泥石-绢云母化带和黏土化-碳酸盐化带。与斑岩型铜钼成矿系统相比,其成矿岩浆岩不仅有花岗斑岩,还有似斑状黑云母花岗岩,矿体在斑岩、花岗岩及上覆火山岩中均有赋存。相较于玻利维亚斑岩型锡成矿带发育的大面积石英-电气石化,锡坑迳斑岩成矿系统更富F,蚀变矿物中出现了大量黄玉、萤石和白云母等。对比国内外典型锡矿床的矿化-蚀变结构和锡石矿物学特征,文章建立了锡坑迳式斑岩型锡成矿系统的找矿模型。 展开更多
关键词 斑岩型锡矿 蚀变分带 原位微量元素分析 成矿系统 锡坑迳矿田
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