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Markov环境下“X”态基于CHSH不等式的量子非局域关联检验 被引量:1
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作者 曾柏云 辜鹏宇 +2 位作者 蒋世民 贾欣燕 樊代和 《物理学报》 SCIE EI CAS CSCD 北大核心 2023年第5期1-9,共9页
量子非局域关联是量子理论最基础的特征之一.“X”态作为实验中常见的一种量子态,因其在演化过程中仍保持“X”形的稳定性,而被广泛应用于开放量子系统的研究中.利用Clauser-Horne-Shimony-Holt (CHSH)不等式,在Markov环境这种典型的开... 量子非局域关联是量子理论最基础的特征之一.“X”态作为实验中常见的一种量子态,因其在演化过程中仍保持“X”形的稳定性,而被广泛应用于开放量子系统的研究中.利用Clauser-Horne-Shimony-Holt (CHSH)不等式,在Markov环境这种典型的开放量子系统下,研究了两种通过局部变换操作所关联的“X”态在振幅阻尼环境和相位阻尼环境中量子非局域检验结果随时间的演化情况.研究结果表明,在相位阻尼环境中,随着演化时间的增加,两种“X”态具有相同的CHSH不等式检验结果.在振幅阻尼环境中,利用局部变换操作得到的“X”态,可获得较长的成功进行量子非局域关联检验的演化时间.最后,详细给出了两种类型“X”态在相位阻尼环境和振幅阻尼环境中成功进行量子非局域关联检验的保真度范围. 展开更多
关键词 量子非局域关联 “x”态 CHSH不等式 相位阻尼 振幅阻尼
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两比特“X”态的量子非局域关联检验 被引量:6
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作者 刘晋 缪波 +1 位作者 胡强 樊代和 《量子光学学报》 北大核心 2020年第1期1-6,共6页
基于Hardy定理,本文针对两比特"X"态这种混合态,进行了量子非局域关联检验研究。首先,简要阐述了针对任意量子态的Hardy定理检验逻辑,并给出了进行量子非局域关联的检验方法。进一步,本文以一种特定的"X"态为例(r=0... 基于Hardy定理,本文针对两比特"X"态这种混合态,进行了量子非局域关联检验研究。首先,简要阐述了针对任意量子态的Hardy定理检验逻辑,并给出了进行量子非局域关联的检验方法。进一步,本文以一种特定的"X"态为例(r=0.47),分析了保真度对"X"态量子非局域关联检验的影响,结果表明,只要该"X"态和量子纯态的保真度F≥0.885时,便能成功地检验量子非局域关联,且随着F的增加,成功检验的程度也将增加。最后,本文还给出了针对任意"X"态(即0<r<1),能够成功进行量子非局域关联检验的"X"态的条件和范围。 展开更多
关键词 “x”态 量子非局域关联 Hardy定理 保真度
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Random noise attenuation by f–x spatial projection-based complex empirical mode decomposition predictive filtering 被引量:7
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作者 马彦彦 李国发 +2 位作者 王钧 周辉 张保江 《Applied Geophysics》 SCIE CSCD 2015年第1期47-54,121,共9页
The frequency–space(f–x) empirical mode decomposition(EMD) denoising method has two limitations when applied to nonstationary seismic data. First, subtracting the first intrinsic mode function(IMF) results in ... The frequency–space(f–x) empirical mode decomposition(EMD) denoising method has two limitations when applied to nonstationary seismic data. First, subtracting the first intrinsic mode function(IMF) results in signal damage and limited denoising. Second, decomposing the real and imaginary parts of complex data may lead to inconsistent decomposition numbers. Thus, we propose a new method named f–x spatial projection-based complex empirical mode decomposition(CEMD) prediction filtering. The proposed approach directly decomposes complex seismic data into a series of complex IMFs(CIMFs) using the spatial projection-based CEMD algorithm and then applies f–x predictive filtering to the stationary CIMFs to improve the signal-to-noise ratio. Synthetic and real data examples were used to demonstrate the performance of the new method in random noise attenuation and seismic signal preservation. 展开更多
关键词 Complex empirical mode decomposition complex intrinsic mode functions f–x predictive filtering random noise attenuation
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INTERFACIAL BONDING IN AS DEPOSITED AND ANNEALED Co/C SOFT X RAY MULTILAYER MIRRORS
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作者 白海力 姜恩永 +1 位作者 王存达 田仁玉 《Transactions of Tianjin University》 EI CAS 1998年第2期80-85,共6页
Interfacial bonding in as deposited and annealed Co/C soft X ray multilayer structures is investigated by X ray photo electron spectroscopy (XPS).It is found that there is interdiffusion between cobalt and carbon ... Interfacial bonding in as deposited and annealed Co/C soft X ray multilayer structures is investigated by X ray photo electron spectroscopy (XPS).It is found that there is interdiffusion between cobalt and carbon in the as deposited Co/C multilayers,and this is confirmed by structure characterization using low angle X ray diffraction (LAXD).The calculation of the chemical shifts in Co C system based on Miedemas macroscopic atom model suggests that it is impossible to detect the chemical shift experimentally in the Co C compound,which is consistent with the XPS results.The presence of metallic carbide bonding is evidenced through the nature of the carbon bonding in survey taken at Co C and C Co interfaces of annealed samples.Our results also indicate that XPS is a direct method to probe the chemical bonding at the interfaces. 展开更多
关键词 soft x ray MULTILAYERS interfacial bonding thermodynamic properties
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XRCC1 genetic polymorphism Arg399Gln and gastric cancer risk:A meta-analysis 被引量:5
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作者 Jian Geng You-Wei Zhang Gui-Chun Huang Long-Bang Chen 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第43期6733-6737,共5页
AIM: To evaluate the association between X-ray crosscomplementing gene 1 (XRCCl) genetic polymorphism Arg399Gln and gastric cancer risk by means of metaanalysis. METHODS: We searched PubMed and NCBI up to June 1, ... AIM: To evaluate the association between X-ray crosscomplementing gene 1 (XRCCl) genetic polymorphism Arg399Gln and gastric cancer risk by means of metaanalysis. METHODS: We searched PubMed and NCBI up to June 1, 2008. A total of 16 clinical trials and reports were identified, but only 8 trials qualified under our selection criteria. Statistical analysis was performed with the software program Review Manage, version 4.2.8. RESULTS: Of the 8 case-control studies selected for this meta-analysis, a total of 1334 gastric cancer cases and 2194 controls were included. For Arg399GIn, the Gin/Gin genotype carriers did not have a decreased cancer risk compared with those individuals with the Arg/Arg genotype (OR = 0.92, 95% CI, 0.71-1.19; P = 0.51). Similarly, no associations were found in the recessive and dominant modeling (Gin/Gin vs Arg/GIn + Arg/Arg: OR = 0.96; 95% CI, 0.77-1.19; P = 0.70 and Gin/Gin + Arg/GIn vs Arg/Arg: OR = 0.90, 95% CI, 0.77-1.05; P = 0.18). CONCLUSION: No association is found between the XRCC1 polymorphism Arg399GIn and gastric cancer risk. 展开更多
关键词 Gastric cancer Gene polymorphism x-ray cross-complementing gene 1 META-ANALYSIS
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Improved random noise attenuation using f-x empirical mode decomposition and local similarity 被引量:6
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作者 甘叔玮 王守东 +3 位作者 陈阳康 陈江龙 钟巍 张成林 《Applied Geophysics》 SCIE CSCD 2016年第1期127-134,220,共9页
Conventional f-x empirical mode decomposition(EMD) is an effective random noise attenuation method for use with seismic profiles mainly containing horizontal events.However,when a seismic event is not horizontal,the... Conventional f-x empirical mode decomposition(EMD) is an effective random noise attenuation method for use with seismic profiles mainly containing horizontal events.However,when a seismic event is not horizontal,the use of f-x EMD is harmful to most useful signals.Based on the framework of f-x EMD,this study proposes an improved denoising approach that retrieves lost useful signals by detecting effective signal points in a noise section using local similarity and then designing a weighting operator for retrieving signals.Compared with conventional f-x EMD,f-x predictive filtering,and f-x empirical mode decomposition predictive filtering,the new approach can preserve more useful signals and obtain a relatively cleaner denoised image.Synthetic and field data examples are shown as test performances of the proposed approach,thereby verifying the effectiveness of this method. 展开更多
关键词 Random noise attenuation f-x empirical mode decomposition local similarity dipping event
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Rapid detection and risk assessment of soil contamination at lead smelting site based on machine learning
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作者 Sheng-guo XUE Jing-pei FENG +5 位作者 Wen-shun KE Mu LI Kun-yan QIU Chu-xuan LI Chuan WU Lin GUO 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第9期3054-3068,共15页
A general prediction model for seven heavy metals was established using the heavy metal contents of 207soil samples measured by a portable X-ray fluorescence spectrometer(XRF)and six environmental factors as model cor... A general prediction model for seven heavy metals was established using the heavy metal contents of 207soil samples measured by a portable X-ray fluorescence spectrometer(XRF)and six environmental factors as model correction coefficients.The eXtreme Gradient Boosting(XGBoost)model was used to fit the relationship between the content of heavy metals and environment characteristics to evaluate the soil ecological risk of the smelting site.The results demonstrated that the generalized prediction model developed for Pb,Cd,and As was highly accurate with fitted coefficients(R~2)values of 0.911,0.950,and 0.835,respectively.Topsoil presented the highest ecological risk,and there existed high potential ecological risk at some positions with different depths due to high mobility of Cd.Generally,the application of machine learning significantly increased the accuracy of pXRF measurements,and identified key environmental factors.The adapted potential ecological risk assessment emphasized the need to focus on Pb,Cd,and As in future site remediation efforts. 展开更多
关键词 smelting site potentially toxic elements x-ray fluorescence potential ecological risk machine learning
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XAF1 is frequently methylated in human esophageal cancer 被引量:10
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作者 Xiang-Yu Chen Qiao-Yu He Ming-Zhou Guo 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第22期2844-2849,共6页
AIM: To explore epigenetic changes in the gene encod- ing X chromosome-linked inhibitor of apoptosis-associ- ated factor 1 (XAF1) during esophageal carcinogenesis. METHODS: Methylation status of XAF1 was detected ... AIM: To explore epigenetic changes in the gene encod- ing X chromosome-linked inhibitor of apoptosis-associ- ated factor 1 (XAF1) during esophageal carcinogenesis. METHODS: Methylation status of XAF1 was detected by methylation-specific polymerase chain reaction (MSP) in four esophageal cancer cell lines (KYSE30, KYSE70, BICl and partially methylated in TE3 cell lines), nine cases of normal mucosa, 72 cases of pri- mary esophageal cancer and matched adjacent tissue. XAF1 expression was examined by semi-quantitative reverse transcriptional polymerase chain reaction and Western blotting before and after treatment with 5-aza- deoxycytidine (5-aza-dc), a demethylating agent. To investigate the correlation of XAF1 expression and methylation status in primary esophageal cancer, immu- nohistochemistry for XAF1 expression was performed in 32 cases of esophageal cancer and matched adjacent tissue. The association of methylation status and clini-copathological data was analyzed by logistic regression. RESULTS: MSP results were as follows: loss of XAF1 expression was found in three of four esophageal cell lines with promoter region hypermethylation (com- pletely methylated in KYSE30, KYSE70 and BIC1 cell lines and partially in TE3 cells); all nine cases of normal esophageal mucosa were unmethylated; and 54/72 (75.00%) samples from patients with esophageal can- cer were methylated, and 25/72 (34.70%) matched adjacent tissues were methylated (75.00% vs 34,70%, z2 = 23.5840, P = 0.000). mRNA level of XAF1 mea- sured with semi-quantitative reverse transcription poly- merase chain reaction was detectable only in TE3 cells, and no expression was detected in KYSE30, KYSE70 or BIC1 cells. Protein expression was not observed in KYSE30 cells by Western blotting before treatment with 5-aza-dc. After treatment, mRNA level of XAF1 was detectable in KYSE30, KYSE70 and BIC1 cells. Protein expression was detected in KYSE30 after treatment with 5-aza-dc. Immunohistochemistry was performed on 32 cases of esophageal cancer and adjacent tissue, and demonstrated XAF1 in the nucleus and cytoplasm. XAF1 staining was found in 20/32 samples of adjacent normal tissue but was present in only 8/32 samples of esophageal cancer tissue (Z2= 9.143, P = 0.002). XAF1 expression was decreased in cancer samples compared with adjacent tissues. In 32 cases of esophageal can- cer, 24/32 samples were methylated, and 8/32 esopha- geal cancer tissues were unmethylated. XAF1 staining was found in 6/8 samples of unmethylated esophageal cancer and 2/24 samples of methylated esophageal cancer tissue. XAF1 staining was inversely correlated with XAF1 promoter region methylation (Fisher's exact test, P = 0.004). Regarding methylation status and clinicopathological data, no significant differences were found in sex, age, tumor size, tumor stage, or metas- tasis with respect to methylation of XAF1 for the 72 tis- sue samples from patients with esophageal cancer. CONCLUSION: XAF1 is frequently methylated in eso- phageal cancer, and XAF1 expression is regulated by promoter region hypermethylation. 展开更多
关键词 x chromosome-linked inhibitor of apoptosis-associated factor 1 Esophageal cancer METHYLATION Methylation-specific polymerase chain reaction Semi-quantitative reverse transcriptional polymerase chainreaction
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Effect of rolling temperature on microstructure and texture of twin roll cast ZK60 magnesium alloy 被引量:2
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作者 陈洪美 于化顺 +2 位作者 Suk-bong KANG 闵光辉 金云学 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第11期2086-2091,共6页
Twin roll cast ZK60 alloy strip/sheet with final thickness of 0.5 mm was prepared, and effect of rolling temperature on microstructure and texture development was investigated using OM and XRD technique, microstructur... Twin roll cast ZK60 alloy strip/sheet with final thickness of 0.5 mm was prepared, and effect of rolling temperature on microstructure and texture development was investigated using OM and XRD technique, microstructure and texture were measured on specimens subjected to rolling experiment at different rolling temperature, and macrotexture was also evaluated by X-ray diffraction method. In addition, the (1010)and (0002) pole figures were measured, and the tensile test was performed to reveal the influence of rolling temperature on mechanical properties. The results show that the microstrucmre of ZK60 alloy sheet consisted of fibrous structure with elongated grains, and shear bands along the rolling direction after warm rolling. Dynamic recrystallization could be found during the warm rolling process at rolling temperature 350℃ and above. And many fine recrystallized grain could be observed in the shear bands area. It is a little difficult to see the recrystallized grain in the sheet warm rolled at 300℃ because of higher density of shear bands. The warm rolled ZK60 alloy sheet exhibited strong (0002) pole texture, the intensity of (0002) pole figure decreases with the increasing of rolling temperature and the basal pole tilted slightly to the transverse direction after warm rolling. 展开更多
关键词 warm rolling MICROSTRUCTURE macrotexture pole figure ZK60 alloy
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Investigation of Temperature Dependency of Morphological Properties of Thermoplastic Polyurethane using WAXS and SAXS Monitoring 被引量:1
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作者 Steffen Thomas Witzleben Katharina Walbrueck +1 位作者 Stephanie Elisabeth Klein Margit Schulze 《Journal of Chemistry and Chemical Engineering》 2015年第8期494-499,共6页
Polyether and polyether/ester based TPU (thermoplastic polyurethanes) were investigated with wide-angle XRD (X-ray diffraction) and SAXS (small angle X-ray scattering). Furthermore, SAXS measurements were perfor... Polyether and polyether/ester based TPU (thermoplastic polyurethanes) were investigated with wide-angle XRD (X-ray diffraction) and SAXS (small angle X-ray scattering). Furthermore, SAXS measurements were performed in the temperature range of 30 ℃ to 130 ℃. Polyether based polymers exhibit only one broad diffraction signal in a region of 2 θ 15° to 25°. In case of polyurethanes with ether/ester modification, the broad diffraction signal arises with small sharp diffraction signals. SAXS measurements of polymers reveal the size and shape of the crystalline zones of the polymer. Between 30 ℃ and 130 ℃ the size of the crystalline zone changes significantly. The size decreases in most of investigated TPU. In the case of Desmopan 9365D an increase of the particle size was observed. 展开更多
关键词 Thermoplastic polyurethanes MORPHOLOGY mechanical properties SAxS WAxS temperature influence CRYSTALLINITY
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Effect of Oleic Acid Tris-(2-hydroxyethyl) isocyanurate Phosphate Ester on Biodegradability and Tribological Performance of Mineral Lubricating Oil 被引量:1
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作者 Ding Jianhua Fang Jianhua +3 位作者 Chen Boshui Zhang Nan Fan Xingyu Zheng Zhe 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2018年第2期97-103,共7页
The oil solubility of synthetic oleic acid tris-(2-hydroxyethyl) isocyanurate phosphate ester(abbreviated as OHTP hereinafter) and its influence on the biodegradability and tribological performance of 400 SN mineral o... The oil solubility of synthetic oleic acid tris-(2-hydroxyethyl) isocyanurate phosphate ester(abbreviated as OHTP hereinafter) and its influence on the biodegradability and tribological performance of 400 SN mineral oil were investigated on a tester and a four-ball tribotester,respectively,for fast evaluating the biodegradability of lubricants.Furthermore,the morphologies and tribochemical species of the worn surfaces lubricated by OHTP-doped oil were studied by scanning electron microscope(SEM) and X-ray photoelectron spectroscope(XPS).The results indicated that OHTP possessed good oil solubility and could improve obviously the biodegradability,the extreme pressure properties,the anti-wear properties and friction-reducing properties of the 400 SN mineral oil.The analytical results of XPS spectra showed that the composite boundary lubrication films were mainly composed of absorbed films and tribochemical species such as FePO-4,Fe_3(PO_4)_2,Fe_2O_3 and Fe_3O_4,which contributed to improving the tribological performances. 展开更多
关键词 ADDITIVE BIODEGRADATION friction wear extreme pressure property
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PATHOLOGICAL AND MORPHOLOGICAL RESEARCH OF EXPERIMENTAL ACETABULAR DYSPLASIA
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作者 张自明 马瑞雪 +1 位作者 吉士俊 牛之彬 《Journal of Shanghai Second Medical University(Foreign Language Edition)》 2004年第1期33-36,41,共5页
Objective To investigate the pathological mechanism of hip dysplasia. Methods The leftknee joints of eighteen rabbits were fixed in extending position with plaster cylinder for four weeks, but their hip joints were fl... Objective To investigate the pathological mechanism of hip dysplasia. Methods The leftknee joints of eighteen rabbits were fixed in extending position with plaster cylinder for four weeks, but their hip joints were flexed. The right side served as control. Roentgenogram was made in all animals. The changes of the x-ray films and the pathological findings between left and right hips were compared. Results Appearance of hip dysplasia was obvious at four weeks after plaster fixation. There were pathological changes, including shallow ace-tabulum and flat femoral head, increased acetabular index and decreased acetabular head index on the x-ray films. Conclusion The hip dysplasia is the result of prolonged extending position of the knee joint. Abnormal knee posture seems to be one of the important factors of hip dysplasia. This kind of deformation may be worsened with time. 展开更多
关键词 acetabular dysplasia animal model pathology morphology
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Solvothermal Route to Prepare the Metastable Phase 3c-Fe_7S_8 with Hexagonal Platelet Morphology
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作者 Xian Yun +3 位作者 XU Xiao Guang LI 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第1期83-86,共4页
The metastable phase 3c-Fe7S8 with the hexagonal platelet morphology has been prepared by using solvothermal route. The product was characterized by means of X-ray powder diffraction (XRD) and transmission electron mi... The metastable phase 3c-Fe7S8 with the hexagonal platelet morphology has been prepared by using solvothermal route. The product was characterized by means of X-ray powder diffraction (XRD) and transmission electron microscopy (TEM) and X-ray photoelectron spectra (XPS). The experiment results show that the as-prepared Fe7S8 is a metastable phase with the hexagonal platelet morphology. 展开更多
关键词 c-Fe_7S_8 solvothermal route hexagonal platelet.
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Physiological Adaptation of Habitat by Ion Distribution in the Leaves of Four Ecotypes of Reed (Phragmites australis) 被引量:9
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作者 郑文菊 陈国仓 +3 位作者 张承烈 胡玉熹 李凌浩 林金星 《Acta Botanica Sinica》 CSCD 2002年第1期82-87,共6页
The ion levels in the epidermal bulliform cells of epidermis, mesophyll cells and cells of the vascular bundle sheath of four ecotypes of reed (Phragmites australis (Cav.) Trin. ex Steud.) were determined by means of ... The ion levels in the epidermal bulliform cells of epidermis, mesophyll cells and cells of the vascular bundle sheath of four ecotypes of reed (Phragmites australis (Cav.) Trin. ex Steud.) were determined by means of X_ray microanalysis. The results indicated that higher K +, Na +, Ca 2+ , Mg 2+ and Cl - were distributed in the vascular bundle sheath cells than in mesophyll cells and epidermal bulliform cells of the swamp ecotype. Higher Ca 2+ was found in the bulliform cells than in mesophyll cells and vascular bundle sheath cells, higher Mg 2+ in the mesophyll cells and higher K +, Na + and Cl - in the vascular bundle sheath cells of the dune ecotype. Higher Na + and Mg 2+ was determined in the mesophyll cells than in the bulliform cells and vascular bundle sheath cells, and higher K +, Ca 2+ and Cl - in the vascular bundle sheath cells of the light salt meadow ecotype. In the heavy salt meadow ecotype, higher Na + and Mg 2+ were accumulated in the bulliform cells than in mesophyll cells and vascular bundle sheath cells, but higher K +, Ca 2+ and Cl - in the mesophyll cells. Furthermore, the distributional conditions of the above five ions in leaf cells of the four ecotypes and their significance in the physiological adaptation of reed to habitat were discussed in detail. 展开更多
关键词 reed ( Phragmites australis ) ion distribution physiological adaptation ECOTYPES x_ray micro_analysis
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Void defect detection in BGA solder joints using mathematical morphology
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作者 张俊生 王明泉 +2 位作者 王玉 王军 郭晋秦 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2017年第2期199-204,共6页
Voids are one of the major defects in ball grid array (BGA) solder joints due to a large amount of outgassing flux that gets entrapped during reflow. X-ray nondestructive machines are used to make voids visible ... Voids are one of the major defects in ball grid array (BGA) solder joints due to a large amount of outgassing flux that gets entrapped during reflow. X-ray nondestructive machines are used to make voids visible as lighter areas inside the solder joints in X-ray images for detection However, it has always been difficult to analyze this problem automatically because of some challenges such as noise, inconsistent lighting and void-like artifacts. This study realized accurate extraction and automatic a-nalysis of void defects in solder joints by adopting a technical proposal, in which Otsu algorithm was used to segment solder balls and void defects were extracted through opening and closing operations and top-hat transformation in mathematical mor-phology. Experimental results show that the technical proposal mentioned here has good robustness and can be applied in the detection of voids in BGA solder joints. 展开更多
关键词 ball grid array (BGA) void defect x-RAY OTSU mathematical morphology
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New Approach for Calculating Tomograms of Quantum States by Virtue of the IWOP Technique 被引量:4
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作者 FAN Hong-Yi WANG Ji-Suo 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第3期431-436,共6页
We show that for tomographic approach there exist two mutual conjugate quantum states [p,σ, τ) and [x,μ, ν) (named the intermediate coordinate-momentum representation), and the two Radon transforms of the Wign... We show that for tomographic approach there exist two mutual conjugate quantum states [p,σ, τ) and [x,μ, ν) (named the intermediate coordinate-momentum representation), and the two Radon transforms of the Wigner operator are just the pure-state density matrices [p)σ1τσ1τ (p| and (p)λ,ν,λ,ν,(x| respectively. As a result, the tomogram of quantum states can be considered as the module-square of the states' wave function in these two representations. Throughout the paper we fully employ the technique of integration within an ordered product of operators. In this way we establish a new convenient formalism of quantum tomogram. 展开更多
关键词 TOMOGRAM intermediate coordinate-momentum representation
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Micromorphological Aspects of Two Forest Soils Development Derived from Igneous Rocks in Lahijan, Iran 被引量:1
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作者 Hasan RAMEZANPOUR Masoumeh POURMASOUMI 《Journal of Mountain Science》 SCIE CSCD 2012年第5期646-655,共10页
In order to characterize various micromorphologic properties of two forest soils derived from different parent rocks in Lahijan, and use the data collected from micromorphological analysis to interpret dominant pedoge... In order to characterize various micromorphologic properties of two forest soils derived from different parent rocks in Lahijan, and use the data collected from micromorphological analysis to interpret dominant pedogenic processes. Two representative soil pedons, granite (P1) and andesitic basalt (P2) were selected in a mountain landform with northwest aspect. Samples for thin section preparation were taken from each horizon by Kubiena boxes or clods. Micromorphological analysis of soils derived from these two soil pedons in eastern part of Lahijan (northern Iran) were conducted based on the physicochemical and mineralogical data. Micromorphological properties were characterized using a polarized light microscope under plain and cross light. Thin section study indicated that the nature of the parent material clearly affected the content of clay formation. It also showed that clay accumulation in the Bt horizons was not only due to clay illuviation (argillan), but that strong in situ weathering of primary minerals also contributed to the enrichment of clay in soils derived from andesitic basalt. Comparing the results of clay mineralogy obtained from X-ray diffraction (XRD) with microscopic studies revealed that birefringence fabric (b-fabric) of the groundmass was partly striated due to smectitic minerals in soil of andesitic basalt (Hapludalf), whereas speckled birefringence fabric was dominant in soil of granite (Udorthent) because of the absence of these minerals. We speculate that pores of skeletal fragments or microcracks in P1 were a place for illuvial clay protection. However, the main factor for flluvial clay film disruption (striation anddeformation) was biological activity (faunal turbation and root pressure) in P1 and expandable minerals and faunal turbation in P2. 展开更多
关键词 Igneous rocks Illuviation Lahijan Soilmicromorphology GRANITE Andesitic basalt
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Hydrothermal Synthesis of Molybdenum Disulfide for Lithium Ion Battery Applications 被引量:11
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作者 WANG Shiquan LI Guohua +4 位作者 DU Guodong JIANG Xueya FENG Chuanqi GUO Zaiping KIM Seung-Joo 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2010年第6期910-913,共4页
Molybdenum disulfide nanoflakes were synthesized by a simple hydrothermal process using sodium molybdate and thiourea as reactants at a relatively low temperature. X-ray diffraction(XRD) and transmission elec-tron mic... Molybdenum disulfide nanoflakes were synthesized by a simple hydrothermal process using sodium molybdate and thiourea as reactants at a relatively low temperature. X-ray diffraction(XRD) and transmission elec-tron microscopy(TEM) indicate that the samples have the structure of 2H-MoS2 and the morphology of nanoflakes with the average thickness around 5-10 nm. The results of electrochemical properties indicate that the morphology and size of MoS2 particles have effects on their capacity when they are used as the anode for lithium ion battery. The as-prepared MoS2 samples have high reversible discharge capacity up to 994.6 mA·h·g-1 for the MoS2-1 elec-trode and 930.1 mA·h·g-1 for the MoS2-2 electrode and show excellent cycling performances. The MoS2-1 electrode has a better cycling stability than the MoS2-2 electrode due to their difference in the uniformity of the samples. 展开更多
关键词 molybdenum disulfide chemical synthesis electrochemical property electrode material
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Biocidal Effect of Gamma Radiation on the Ecology of Filamentous Fungal Populations Associated with Stone Deterioration
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作者 Douglas Boniek Isolda de Castro Mendes +1 位作者 Antonio Femando Batista dos Santos Maria Aparecida de Resende Stoianoff 《Journal of Environmental Science and Engineering(A)》 2017年第5期252-259,共8页
This study focused on the identification of the filamentous fungi associated with soapstone samples exposed to outdoor conditions and the biocidal effect of gamma radiations on isolated fungal populations in Minas Ger... This study focused on the identification of the filamentous fungi associated with soapstone samples exposed to outdoor conditions and the biocidal effect of gamma radiations on isolated fungal populations in Minas Gerais State in Brazil. Two soapstone blocks were placed outdoors under tropical environmental conditions for 12 months. A total of 9 filamentous fungal populations were identified on their surfaces, namely Acremomium (cf.) alternatum, Alternaria alternata, Aspergillusfumigatus, Calcarisporium (cf.) arbuscula, Cladosporium cladosporioides, Curvularia lunata, Epicoccum nigrum, Fusarium equiseti and Penicillium citrinum. The gamma radiation assay was then carried out as a test of biocidal action by exposing all fungal populations to the ionizing radiation. The results showed that only the C. cladosporioides species was resistant to this biocidal agent, since it was able to increase its population post exposure. Scanning electron microscopy images identified the microbial colonization on the soapstone blocks and the stone elementar composition was analyzed by energy dispersive X-ray spectrometry. After treatment, there was no structural and aesthetic alteration in the soapstone samples, and evidencing that gamma radiation can be used as a biocidal agent. However, the resistance of the black fungal population indicates caution in the choice of gamma irradiation as biocidal treatment. 展开更多
关键词 Gamma radiation biocidal STONE ECOLOGY filamentous fungi.
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Robust superconductivity and transport properties in (Li_(1-x)Fe_x)OHFeSe single crystals 被引量:1
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作者 Hai Lin Jie Xing +2 位作者 Xi Yu Zhu Huan Yang Hai-Hu Wen 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2016年第5期11-15,共5页
The recently discovered(Li_(1-x) Fe_x)OHFe Se superconductor with T c about 40 K provides a good platform for investigating the magnetization and electrical transport properties of Fe Se-based superconductors. By usin... The recently discovered(Li_(1-x) Fe_x)OHFe Se superconductor with T c about 40 K provides a good platform for investigating the magnetization and electrical transport properties of Fe Se-based superconductors. By using a hydrothermal ion-exchange method,we have successfully grown crystals of(Li_(1-x) Fe_x)OHFe Se. X-ray diffraction on the sample shows the single crystalline Pb O-type structure with the c-axis preferential orientation. Magnetic susceptibility and resistive measurements show an onset superconducting transition at around T c=38.3 K. Using the magnetization hysteresis loops and Bean critical state model, a large critical current J s is observed in low temperature region. The critical current density is suppressed exponentially with increasing magnetic field.Temperature dependencies of resistivity under various currents and fields are measured, revealing a robust superconducting current density and bulk superconductivity. 展开更多
关键词 iron chalcogenides critical currents magnetic properties transport properties
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