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Probe into the Internal Roots of Anna Karenina's Tragedy
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作者 杨华 《科技信息》 2014年第7期147-147,144,共2页
Anna was a vivid literature figure in the international literature history. Besides the obvious social factors of Anna 's tragedy, some internal roots of her tragedy shouldn't be neglected, such as her particu... Anna was a vivid literature figure in the international literature history. Besides the obvious social factors of Anna 's tragedy, some internal roots of her tragedy shouldn't be neglected, such as her particular spiritual world, merit and drawback of her character, her love value and conflicts about her thought. Analyzing into internal factors for Anna 's tragedy would offer further appreciation to readers. 展开更多
关键词 ANNA TRAGEDY INTERNAL ROOTS probe
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A Novel Method for Determining the Void Fraction in Gas-Liquid Multi-Phase Systems Using a Dynamic Conductivity Probe
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作者 Xiaochu Luo Xiaobing Qi +3 位作者 Zhao Luo Zhonghao Li Ruiquan Liao Xingkai Zhang 《Fluid Dynamics & Materials Processing》 EI 2024年第6期1233-1249,共17页
Conventional conductivity methods for measuring the void fraction in gas-liquid multiphase systems are typically affected by accuracy problems due to the presence of fluid flow and salinity.This study presents a novel... Conventional conductivity methods for measuring the void fraction in gas-liquid multiphase systems are typically affected by accuracy problems due to the presence of fluid flow and salinity.This study presents a novel approach for determining the void fraction based on a reciprocating dynamic conductivity probe used to measure the liquid film thickness under forced annular-flow conditions.The measurement system comprises a cyclone,a conductivity probe,a probe reciprocating device,and a data acquisition and processing system.This method ensures that the flow pattern is adjusted to a forced annular flow,thereby minimizing the influence of complex and variable gas-liquid flow patterns on the measurement results;Moreover,it determines the liquid film thickness solely according to circuit connectivity rather than specific conductivity values,thereby mitigating the impact of salinity.The reliability of the measurement system is demonstrated through laboratory experiments.The experimental results indicate that,in a range of gas phase superficial velocities 5–20 m/s and liquid phase superficial velocities 0.079–0.48 m/s,the maximum measurement deviation for the void fraction is 4.23%. 展开更多
关键词 Forced annular flow dynamic conductivity probe void fraction gas-liquid flow liquid film thickness
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A Tentative Probe into the Solution of the Listening Problems 被引量:1
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作者 王昭昭 《英语广场(学术研究)》 2012年第2期98-99,共2页
Many students often raise questions, "Why it is so difficult to improve the listening comprehension?" This cannot be solved easily, because listening is a kind of complex and perceptual knowledge process. Li... Many students often raise questions, "Why it is so difficult to improve the listening comprehension?" This cannot be solved easily, because listening is a kind of complex and perceptual knowledge process. Listening does not only mean the ability to hear, it is also the ability to capture the information that the language carries through hearing organs and the ability of head. As far as I am concerned, such a problem is related to the complexity of various factors: listening itself covers, the language knowledge proficiency listeners possess, and also it is closely connected with the traditional foreign language style. 展开更多
关键词 A Tentative probe into the Solution of the Listening Problems
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Solving the Olbers’s Paradox, Explaining the “Red-Shift”, and Challenging the Relativities by “Sun Matters Theory” and “Sun Model of Universe”, an Evolution of the Einstein’s Static Universe Model
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作者 Wanpeng Sun 《Natural Science》 2024年第2期7-18,共12页
Olbers’s paradox, known as the dark night paradox, is an argument in astrophysics that the darkness of the night sky conflicts with the assumption of an infinite and eternal static universe. Big-Bang theory was used ... Olbers’s paradox, known as the dark night paradox, is an argument in astrophysics that the darkness of the night sky conflicts with the assumption of an infinite and eternal static universe. Big-Bang theory was used to partially explain this paradox, while introducing new problems. Hereby, we propose a better theory, named Sun Matters Theory, to explain this paradox. Moreover, this unique theory supports and extended the Einstein’s static universe model proposed by Albert Einstein in 1917. Further, we proposed our new universe model, “Sun Model of Universe”. Based on the new model and novel theory, we generated innovative field equation by upgrading Einstein’s Field Equation through adding back the cosmological constant, introducing a new variable and modifying the gravitationally-related concepts. According to the Sun Model of Universe, the dark matter and dark energy comprise the so-called “Sun Matters”. The observed phenomenon like the red shift is explained as due to the interaction of ordinary light with Sun Matters leading to its energy and frequency decrease. In Sun Model, our big universe consists of many universes with ordinary matter at the core mixed and surrounded with the Sun Matters. In those universes, the laws of physics may be completely or partially different from that of our ordinary universe with parallel civilizations. The darkness of night can be easily explained as resulting from the interaction of light with the Sun Matters leading to the sharp decrease in the light intensity. Sun Matters also scatter the light from a star, which makes it shining as observed by Hubble. Further, there is a kind of Sun Matters named “Sun Waters”, surrounding every starts. When lights pass by the sun, the Sun Waters deflect the lights to bend the light path. According to the Sun Model, it is the light bent not the space bent that was proposed in the theory of relativities. 展开更多
关键词 Olbers’s Paradox Sun matters theory Sun Model of Universe Einstein’s Universe Dark Mass
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Controllable Synthesis of Au NRs and Its Flexible SERS Optical Fiber Probe with High Sensitivity
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作者 熊文豪 WANG Wenbo +1 位作者 LONG Yuting 李宏 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第1期7-16,共10页
The surface-enhanced Raman scattering(SERS) optical fiber probes were successfully prepared by self-assembling on polyelectrolyte multilayers. Gold nanorods(Au NRs) were used as SERS enhancement material to give excel... The surface-enhanced Raman scattering(SERS) optical fiber probes were successfully prepared by self-assembling on polyelectrolyte multilayers. Gold nanorods(Au NRs) were used as SERS enhancement material to give excellent biological affinity and stability to the SERS optical fiber probes. Au NRs were synthesized by seed growth method. The synergistic effect between AgNO_(3) and surfactant was investigated, and the highest yield was found when AgNO_(3) was 500 uL. Meanwhile, different SERS optical fiber probes were obtained by selecting silane coupling agent, polyelectrolyte multilayer and graphene oxide(GO) to treat quartz fiber. It was found that the SERS optical fiber probes obtained by the self-assembled on polyelectrolyte multilayers method performed better than those by other methods. In addition, Mapping was combined with finite element simulation to analyze the electromagnetic field distribution at the fiber end face.The electromagnetic field distribution of Au NRs was investigated, the difference of electromagnetic field intensity around the Au NRs with different arrangements was compared, the strongest signal was obtained when the Au NRs were head-to-head. Finally, sensitivity of the optimized SERS optical fiber probes could reach 10^(-9)mol/L, with excellent stability and repeatability. 展开更多
关键词 surface-enhanced Raman scattering(SERS) optical fiber probe gold nanorods(Au NRs) polyelectrolyte multilayers controllable synthesis
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A ratiometric fluorescent probe for hypoxanthine detection in aquatic products based on the enzyme mimics and fluorescence of cobalt-doped carbon nitride
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作者 Xin Wang Chengyi Hong +1 位作者 Zhengzhong Lin Zhiyong Huang 《Food Science and Human Wellness》 SCIE CSCD 2024年第2期879-884,共6页
A ratiometric fluorescent probe for hypoxanthine(Hx)detection was established based on the mimic enzyme and fluorescence characteristics of cobalt-doped graphite-phase carbon nitride(Co doped g-C_(3)N_(4)).In addition... A ratiometric fluorescent probe for hypoxanthine(Hx)detection was established based on the mimic enzyme and fluorescence characteristics of cobalt-doped graphite-phase carbon nitride(Co doped g-C_(3)N_(4)).In addition to emitting strong fluorescence,the peroxidase activity of Co doped g-C_(3)N_(4)can catalyze the reaction of O-phenylenediamine and H_(2)O_(2)to produce diallyl phthalate which can emit yellow fluorescence at 570 nm.Through the decomposition of Hx by xanthine oxidase,Hx can be indirectly detected by the generating hydrogen peroxide based on the measurement of fluorescent ratio I(F_(570)/F_(370)).The linear range was 1.7-272.2 mg/kg(R^(2)=0.997),and the detection limit was 1.52 mg/kg(3σ/K,n=9).The established method was applied to Hx detection in bass,grass carp,and shrimp,and the data were verified by HPLC.The result shows that the established probe is sensitive,accurate,and reliable,and can be used for Hx detection in aquatic products. 展开更多
关键词 Co doped g-C_(3)N_(4) Ratiometric fluorescent probe HYPOXANTHINE FRESHNESS Aquatic products
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Loading calcium fluorescent probes into protoplasts to detect calcium in the flesh tissue cells of Malus domestica
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作者 Lina Qiu Yongzhang Wang Haiyong Qu 《Horticulture Research》 SCIE 2020年第1期1561-1571,共11页
Cytosolic Ca^(2+)plays a key role in signal transduction in plants.Calcium imaging is the most common approach to studying dynamic changes in the cytoplasmic Ca^(2+)content.Here,we used mature‘Fuji’apples(Malus pumi... Cytosolic Ca^(2+)plays a key role in signal transduction in plants.Calcium imaging is the most common approach to studying dynamic changes in the cytoplasmic Ca^(2+)content.Here,we used mature‘Fuji’apples(Malus pumila Mill.)to obtain viable protoplasts from flesh tissue cells by enzymatic hydrolysis;then,three small-molecule fluorescent probes(fluo-8/AM,fluo-4/AM,and rhod-2/AM)were loaded into the protoplasts.All three Ca^(2+)fluorescent probes successfully entered the cytoplasm but did not enter the vacuole.Both the Ca^(2+)chelator(EGTA)and Ca^(2+)channel blocker(La3+)reduced the fluorescence intensity in the cytoplasm.The calcium ionophore A23187 increased the fluorescence intensity in the cytoplasm at 5μmol/L but decreased it at 50μmol/L.Additionally,A23187 reversed the fluorescence intensity in the cytoplasm,which was decreased by La3+.Ionomycin is also a calcium ionophore that can increase the fluorescence intensity of calcium in the cytoplasm.These results suggest that small-molecule Ca^(2+)fluorescent probes can be used to detect changes in cytosolic calcium levels in the cells of fruit flesh tissue.In addition,the optimum concentration of fluo-8/AM was determined to be 5μmol/L.This was the first time that protoplasts have been isolated from apple flesh tissue cells and small-molecule fluorescent probes have been used to detect calcium in the cytoplasm of flesh tissue cells.This study provides a new method to study calcium signal transduction in fruit flesh tissue. 展开更多
关键词 reversed probes HYDROLYSIS
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The pivotal role of microglia in injury and the prognosis of subarachnoid hemorrhage
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作者 Wenjing Ning Shi Lv +1 位作者 Qian Wang Yuzhen Xu 《Neural Regeneration Research》 SCIE CAS 2025年第7期1829-1848,共20页
Subarachnoid hemorrhage leads to a series of pathological changes,including vascular spasm,cellular apoptosis,blood–brain barrier damage,cerebral edema,and white matter injury.Microglia,which are the key immune cells... Subarachnoid hemorrhage leads to a series of pathological changes,including vascular spasm,cellular apoptosis,blood–brain barrier damage,cerebral edema,and white matter injury.Microglia,which are the key immune cells in the central nervous system,maintain homeostasis in the neural environment,support neurons,mediate apoptosis,participate in immune regulation,and have neuroprotective effects.Increasing evidence has shown that microglia play a pivotal role in the pathogenesis of subarachnoid hemorrhage and affect the process of injury and the prognosis of subarachnoid hemorrhage.Moreover,microglia play certain neuroprotective roles in the recovery phase of subarachnoid hemorrhage.Several approaches aimed at modulating microglia function are believed to attenuate subarachnoid hemorrhage injury.This provides new targets and ideas for the treatment of subarachnoid hemorrhage.However,an in-depth and comprehensive summary of the role of microglia after subarachnoid hemorrhage is still lacking.This review describes the activation of microglia after subarachnoid hemorrhage and their roles in the pathological processes of vasospasm,neuroinflammation,neuronal apoptosis,blood–brain barrier disruption,cerebral edema,and cerebral white matter lesions.It also discusses the neuroprotective roles of microglia during recovery from subarachnoid hemorrhage and therapeutic advances aimed at modulating microglial function after subarachnoid hemorrhage.Currently,microglia in subarachnoid hemorrhage are targeted with TLR inhibitors,nuclear factor-κB and STAT3 pathway inhibitors,glycine/tyrosine kinases,NLRP3 signaling pathway inhibitors,Gasdermin D inhibitors,vincristine receptorαreceptor agonists,ferroptosis inhibitors,genetic modification techniques,stem cell therapies,and traditional Chinese medicine.However,most of these are still being evaluated at the laboratory stage.More clinical studies and data on subarachnoid hemorrhage are required to improve the treatment of subarachnoid hemorrhage. 展开更多
关键词 apoptosis blood–brain barrier brain edema MICROGLIA NEUROINFLAMMATION neuron NEUROPROTECTION subarachnoid hemorrhage VASOCONSTRICTION white matter injury
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An insight into the in vivo imaging potential of curcumin analogues as fluorescence probes
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作者 Yu Liu Chuang Zhang +3 位作者 Hao Pan Li Li Yanjie Yu Bingmi Liu 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2021年第4期419-431,共13页
Curcumin and its derivatives have good electrical and optical properties due to the highly symmetric structure of delocalized π electrons. Apart from that, curcumin and its derivatives can interact with numerous mole... Curcumin and its derivatives have good electrical and optical properties due to the highly symmetric structure of delocalized π electrons. Apart from that, curcumin and its derivatives can interact with numerous molecular targets, thereby exerting less side effects on human body. The fluorescence emission wavelength and fluorescence intensity of curcumin can be enhanced by modifying its π-conjugated system and β-diketone structure. Some curcumin-based fluorescent probes have been utilized to detect soluble/insoluble amyloid-β protein, intracranial reactive oxygen species, cysteine, cancer cells, etc. Based on the binding characteristics of curcumin-based fluorescent probes with various target molecules, the factors affecting the fluorescence intensity and emission wavelength of the probes are analyzed, in order to obtain a curcumin probe with higher sensitivity and selectivity. Such an approach will be greatly applicable to in vivo fluorescence imaging. 展开更多
关键词 CURCUMIN Fluorescent probe Fluorescence characteristics Structural feature
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The Polarization Potential as a Probe into Interstellar Matter
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作者 Amaury de Kertanguy 《Journal of Applied Mathematics and Physics》 2021年第11期2623-2640,共18页
By simple arguments, it is shown how alkaline types of atoms can be seen in dense molecular clouds depending on the average temperature of such regions of the Universe. This paper predicts infrared lines of such atoms... By simple arguments, it is shown how alkaline types of atoms can be seen in dense molecular clouds depending on the average temperature of such regions of the Universe. This paper predicts infrared lines of such atoms that could be seen in molecular clouds. The theory is developed in the first part and the predicted experimental results will follow. It results that the alkaline atoms modelized using the short-range polarization potential are found in quantum states <em>n</em><sub>*</sub> > 2. 展开更多
关键词 Interstellar Matter Alkaline Atoms Giant Molecular Clouds
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THEORY OF LC BIOMEMBRANE——A PROBE INTO SOFT CONDENSED MATTER PHYSICS
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作者 Ouyang Zhongcan(Institute of Theoretical Physics, CAS) 《Bulletin of the Chinese Academy of Sciences》 1999年第3期154-157,共4页
Soft condensed-state physics is a disciplinary frontier of 20th-century physics. An interdiscipline in nature, it involves biology, chemistry and even pure mathematics. Taking the liquid crystal (LC) biomembrane as an... Soft condensed-state physics is a disciplinary frontier of 20th-century physics. An interdiscipline in nature, it involves biology, chemistry and even pure mathematics. Taking the liquid crystal (LC) biomembrane as an example, this article expounds the current development trend of this new and promising branch of contemporary physics. 展开更多
关键词 PRO LC theORY OF LC BIOMEMBRANE A probe into SOFT CONDENSED MATTER PHYSICS
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A PROBE INTO THE NO.1 MONASTERY IN TIBER
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《China's Tibet》 2000年第3期42-43,共2页
关键词 NO A probe into the NO.1 MONASTERY IN TIBER
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Media and Human Rights Education——A Probe into the Possibility of News Coverage from the Viewpoint of the Human Rights Framework
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作者 BU WEI 《The Journal of Human Rights》 2013年第5期27-31,共5页
At the present time, mass me- dia and new media play an important part in establish- ing and constructing a civil society. This paper will focus on educa- tional roles of the media and will probe the major experiences... At the present time, mass me- dia and new media play an important part in establish- ing and constructing a civil society. This paper will focus on educa- tional roles of the media and will probe the major experiences and challenges related to constructing news events with human rights as the framework. 展开更多
关键词 A probe into the Possibility of News Coverage from the Viewpoint of the Human Rights Framework Media and Human Rights Education
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Analysis of the Sensitivity of Probe EUB338 for Enumerating Eubacterial Cells 被引量:1
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作者 王晓丹 《Agricultural Science & Technology》 CAS 2011年第10期1430-1432,共3页
[Objective] This paper aimed to improve the detection rate of probe EUB338 for eubacteria.[Methods] Sixteen strains were used as materials for the experiment and analyzed through fluorescence in situ hybridization.[Re... [Objective] This paper aimed to improve the detection rate of probe EUB338 for eubacteria.[Methods] Sixteen strains were used as materials for the experiment and analyzed through fluorescence in situ hybridization.[Result] The average detection rate of probe EUB338 was 63.9%,which can be increased to 71.3% through modified FISH.[Conclusion] This research was able to provide scientific basis for the detection of eubacteria in soil from the perspective of molecular biology. 展开更多
关键词 EUB338 Modified FISH Detection rate of probe
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英汉笔译课程PROBE教学模式探究
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作者 陈严春 《忻州师范学院学报》 2024年第2期114-118,共5页
作为本科翻译专业的一门核心课程,英汉笔译课程在培养学生英汉双语运用能力、翻译能力和跨文化能力,尤其是学生英译汉翻译实践能力作用明显。文章对“PROBE教学模式”进行概念诠释,从教学目标、课程设计、教学过程和学习评价四个方面探... 作为本科翻译专业的一门核心课程,英汉笔译课程在培养学生英汉双语运用能力、翻译能力和跨文化能力,尤其是学生英译汉翻译实践能力作用明显。文章对“PROBE教学模式”进行概念诠释,从教学目标、课程设计、教学过程和学习评价四个方面探讨了“PROBE教学模式”在英汉笔译课程中的应用,最后提出几点建议,以期提高英汉笔译课程的教学效果。 展开更多
关键词 英汉笔译 probe教学模式 教学效果
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Probe based confocal laser endomicroscopy of the pancreatobiliary system 被引量:6
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作者 Majid A Almadi Helmut Neumann 《World Journal of Gastroenterology》 SCIE CAS 2015年第44期12696-12708,共13页
AIM:To review applications of confocal laser endomicroscopy(CLE) in pancreatobiliary lesions and studies that assessed training and interpretation of images. METHODS: A computerized literature search was performed usi... AIM:To review applications of confocal laser endomicroscopy(CLE) in pancreatobiliary lesions and studies that assessed training and interpretation of images. METHODS: A computerized literature search was performed using OVID MEDLINE, EMBASE, Cochrane library, and the ISI Web of Knowledge from 1980 to October 2014. We also searched abstracts from major meetings that included the Digestive Disease Week, Canadian Digestive Disease Week and the United European Gastroenterology Week using a combination of controlled vocabulary and text words related to p CLE, confocal, endomicroscopy, probe-based confocal laser endomicroscopy, and bile duct to identify reports of trials. In addition, recursive searches and crossreferencing was performed, and manual searches of articles identified after the initial search was also completed. We included fully published articles and those in abstract form. Given the relatively recent introduction of CLE we included randomized trials and cohort studies.R E S U LT S : In the evaluation of indeterminate pancreatobiliary strictures CLE with ERCP compared to ERCP alone can increase the detection of cancerous strictures with a sensitivity of(98% vs 45%) andhas a negative predictive value(97% vs 69%), but decreased the specificity(67% vs 100%) and the positive predictive value(71% vs 100%) when compared to index pathology. Modifications in the classification systems in indeterminate biliary strictures have increased the specificity of p CLE from 67% to 73%. In pancreatic cystic lesions there is a need to develop similar systems to interpret and characterize lesions based on CLE images obtained. The presence of superficial vascular network predicts serous cystadenomas accurately. Also training in acquiring and interpretation of images is feasible in those without any prior knowledge in CLE in a relatively simple manner and computer-aided diagnosis software is a promising innovation. CONCLUSION: The role of p CLE in the evaluation of pancreatobiliary disorders might be better suited for those with an intermediate and low probability. 展开更多
关键词 probe BASED CONFOCAL laser ENDOMICROSCOPY CONFOCAL
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New insights into the extraction of invisible gold in a low-grade high-sulfur Carlin-type gold concentrate by bio-pretreatment 被引量:4
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作者 Xiao-bin Qiu Jian-kang Wen +3 位作者 Song-tao Huang Hong-ying Yang Mei-lin Liu Biao Wu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2017年第10期1104-1111,共8页
To extract gold from a low-grade(13.43 g/t) and high-sulfur(39.94wt% sulfide sulfur) Carlin-type gold concentrate from the Nibao deposit, Guizhou, a bio-pretreatment followed by carbon-in-pulp(CIP) cyanide leaching pr... To extract gold from a low-grade(13.43 g/t) and high-sulfur(39.94wt% sulfide sulfur) Carlin-type gold concentrate from the Nibao deposit, Guizhou, a bio-pretreatment followed by carbon-in-pulp(CIP) cyanide leaching process was used. Various methods were used to detect the low-grade gold in the concentrate; however, only time-of-flight secondary-ion mass spectrometry(TOF-SIMS) was successful. With bio-pretreatment, the gold recovery rate increased by approximately 70.16% compared with that obtained by direct cyanide leaching of the concentrate. Various attempts were made to increase the final gold recovery rate. However, approximately 20wt% of the gold was non-extractable. To determine the nature of this non-extractable gold, mineralogy liberation analysis(MLA), formation of secondary product during the bio-pretreatment, and the preg-robbing capacity of the carbonaceous matter in the ore were investigated. The results indicated that at least four factors affected the gold recovery rate: gold occurrence, tight junctions of gold-bearing pyrite with gangue minerals, jarosite coating of the ore, and the carbonaceous matter content. 展开更多
关键词 GOLD ore invisible GOLD bio-pretreatment mineralogy LIBERATION analysis secondary product CARBONACEOUS matter
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Distribution and its mechanism of suspended particulate matters in the southern Huanghai Sea and the East China Sea in summer 被引量:3
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作者 QIAO Lulu LIU Yong +3 位作者 CHEN Jiaojie MA Yanyan LI Guangxue SONG Jun 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2011年第5期94-100,共7页
Water temperature,turbidity,chlorophyll-a and suspended sediment concentration (SSC) were investigated at 61 stations of eight sections in the southern Huanghai Sea (HS) and the East China Sea (ECS) during the s... Water temperature,turbidity,chlorophyll-a and suspended sediment concentration (SSC) were investigated at 61 stations of eight sections in the southern Huanghai Sea (HS) and the East China Sea (ECS) during the summer (28 June to 15 July) of 2006.The horizontal distribution of suspended parti culate matter (SPM) displayed a high concentration inshore and a low value offshore.The maximum value can reach 10.4 mg/dm 3,which can be found at the Changjiang River mouth.For the same site,the SSC was generally higher at the bottom than on the surface.In the vertical direction,distribution characteristics of turbidity can be divided into two types:in the southern HS high values at the bottom while low values on the surface,and in the ECS high values inshore with low values offshore.The thermocline in the HS and the Taiwan Warm Current in the ECS could be important factors preventing the SPM from diffusing upward and seaward.Even the typhoon Ewiniar was not able to work on the major sediment transport under the thermocline during the observation. 展开更多
关键词 TURBIDITY suspended particulate matter SUMMER theRMOCLINE warm current
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Probe Selection for Over-the-Air Test in 5G Base Stations with Massive Multiple-Input Multiple-Output 被引量:3
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作者 Xiang Zhang Shangbin Qiao +1 位作者 Mugen Peng Yong Li 《China Communications》 SCIE CSCD 2019年第7期1-12,共12页
In 5G systems, massive multiple-input multiple-output (MIMO) has been adopted in base stations (BSs) to improve spectral efficiency and coverage. The traditional conductive performance test techniques are challenging ... In 5G systems, massive multiple-input multiple-output (MIMO) has been adopted in base stations (BSs) to improve spectral efficiency and coverage. The traditional conductive performance test techniques are challenging due to the unaffordable cost and high complexity when testing a large number of antennas. To solve this problem, the over-the-air (OTA) test has been presented, in which probe selection is the key to reduce the number of channel emulators and probes. In this paper, a novel artificial bee colony (ABC) algorithm is introduced to enhance the efficiency and accuracy of probe selection procedure. A sectoring- based multi-probe anechoic chamber (MPAC) is built to evaluate the throughput performance of massive MIMO equipped in 5G BS. In addition, link level simulation is carried out to evaluate the proposal’s performance gain under the commercial network assumptions, where the average throughput of three velocity is given with different SNR region. The results suggest that OTA chamber and multi-probe wall are available not only for 5G BSs, but also for user equipments (UEs) with end-to-end communication. 展开更多
关键词 anechoic chamber MASSIVE MIMO base stations over-the-air TEST probe SELECTION performance evaluation
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Superconductivity of Lanthanum Superhydride Investigated Using the Standard Four-Probe Configuration under High Pressures 被引量:8
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作者 Fang Hong Liuxiang Yang +7 位作者 Pengfei Shan Pengtao Yang Ziyi Liu Jianping Sun Yunyu Yin Xiaohui Yu Jinguang Cheng Zhongxian Zhao 《Chinese Physics Letters》 SCIE CAS CSCD 2020年第10期83-86,共4页
Recently,the theoretically predicted lanthanum superhydride,LaH 10±δ,with a clathrate-like structure was successfully synthesized and found to exhibit a record high superconducting transition temperature T c≈25... Recently,the theoretically predicted lanthanum superhydride,LaH 10±δ,with a clathrate-like structure was successfully synthesized and found to exhibit a record high superconducting transition temperature T c≈250 K at∼170 GPa,opening a new route for room-temperature superconductivity.However,since in situ experiments at megabar pressures are very challenging,few groups have reported the∼250 K superconducting transition in LaH 10±δ.Here,we establish a simpler sample-loading procedure that allows a relatively large sample size for synthesis and a standard four-probe configuration for resistance measurements.Following this procedure,we successfully synthesized LaH 10±δwith dimensions up to 10×20μm^2 by laser heating a thin La flake and ammonia borane at∼1700 K in a symmetric diamond anvil cell under the pressure of 165 GPa.The superconducting transition at T c≈250 K was confirmed through resistance measurements under various magnetic fields.Our method will facilitate explorations of near-room-temperature superconductors among metal superhydrides. 展开更多
关键词 resistance HYDRIDE probe
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