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Enhanced coking resistance of a Ni cermet anode by a chromates protective layer 被引量:1
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作者 Hong Chang Huili Chen +4 位作者 Guangming Yang Wei Zhou Jianping Bai Sidian Li Zongping Shao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第10期117-125,共9页
Ni-based anodes of SOFCs are susceptible to coking, which greatly limits practical application of direct methane-based fuels. An indirect internal reformer is an effective way to convert methane-based fuels into synga... Ni-based anodes of SOFCs are susceptible to coking, which greatly limits practical application of direct methane-based fuels. An indirect internal reformer is an effective way to convert methane-based fuels into syngas before they reach anode. In this work, catalytic activity of a redox-stable perovskite La0.7Sr0.3Cr0.8Fe0.2O3-δ(LSCrFO) for methane conversion was evaluated. The catalyst was fabricated as an anodic protective layer to improve coking resistance of a Ni cermet anode. Using wet CH4 as a fuel, the LSCrFO-modified cell showed excellent power output and good coking resistance with peak power density of 1.59 W cm-2 at 800℃. The cell demonstrated good durability lasting for at least 100 h. While the bare cell without the protective layer showed poor durability with the cell voltage fast dropped from 0.75 V to 0.4 V within 30 min. Under wet coal bed methane (CBM) operation, obvious performance degradation within 35 h (1.7 mV h^-1) was observed due to the influence of heavy carbon compounds in CBM. The pre-and post-mortem microstructures and carbon analysis of the anode surface and catalyst surface were further conducted. 展开更多
关键词 Solid oxide fuel cell (SOFC) NI CERMET anode Methane-based fuels chromates catalyst COKING RESISTANCE
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Co-minimal Ideal Graphs of Commutative Rings
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作者 ZHANG Guanghui ZHANG Zhizheng 《数学进展》 北大核心 2025年第4期749-758,共10页
Given two ideals I and J of a commutative ring R,there are two extreme connections between I and J:I+J=R and I∩J={0}.For the former case,graphs whose vertices are defined as the proper ideals of R and that two vertic... Given two ideals I and J of a commutative ring R,there are two extreme connections between I and J:I+J=R and I∩J={0}.For the former case,graphs whose vertices are defined as the proper ideals of R and that two vertices are adjacent if and only if their sum is the whole ring R are known as co-maximal ideal graphs.In this paper,we introduce a new kind of graph structure on R,called co-minimal ideal graph,according to the second case:Its vertices are the nonzero ideals of R and two vertices are adjacent if and only if their intersection is zero.Some important graph parameters(including girth,diameter,clique number and chromatic number)and graph structures(including tree and bipartite graph)of co-minimal ideal graphs over finite commutative rings are studied.In particular,we show that the co-maximal ideal graph and the co-minimal ideal graph over R are isomorphic if and only if the number of maximal ideals of R and the number of minimal ideals of R coincide. 展开更多
关键词 minimal ideal DIAMETER clique number chromatic number
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Crown saturation and intrasexual dominance: Evidence of a negatively correlated handicap in male Saffron Finches
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作者 Camilo Ernesto Espinosa James Montoya Lerma +1 位作者 Hector Fabio Rivera-Gutierrez Lorena Cruz-Bernate 《Avian Research》 2025年第2期291-300,共10页
Carotenoid-based plumage coloration may signal individuals' overall body condition, influencing reproduction and survival of birds. In tropical species, little is known about the influence of color on social inter... Carotenoid-based plumage coloration may signal individuals' overall body condition, influencing reproduction and survival of birds. In tropical species, little is known about the influence of color on social interactions and mate attraction. We evaluated the chromatic variation of 136 adult Saffron Finches(Sicalis ffiaveola) in Cali and Jamundí, Colombia. Our aim was to determine whether plumage coloration in this social, abundant, and widely distributed species is a signal used in mate choice and establishment of hierarchies. We predicted that there was intrasexual chromatic variation in crown and throat, and that individuals with higher saturation, regardless of sex, would be preferred by opposite sex and they would be dominant in intrasexual aggressive interactions, reflecting better condition. We quantified the reflectance of the crown and throat with visible and ultraviolet light(300–700 nm) subsequent to the molecular sex determination of each individual. Our results suggest that the chromatic variation in the crown and throat is explained by the perception of medium and long wavelengths in both sexes. Additionally, saturation is the color characteristic that best explains the chromatic variation. We formed duos of individuals based on chromatic contrast and conducted 23 mate choice experiments and 21 dominance experiments. The analysis of spectra and experiments revealed that dominance in males was associated with less saturated crowns. Our results reveal that in the Saffron Finches the “negatively correlated handicap” is a plausible hypothesis. Crown color appears to mediate dominance interactions, with less saturated males potentially taking greater risks to gain access to resources. 展开更多
关键词 Carotenoids Chromatic variation Colombia Social interactions Visual system
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Efficient selenite reduction and chromium resistance by multiple pathways in Bacillus wiedmannii ES2-45 and Se-biofortification in rice by foliar application
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作者 Fang Ma Tiantian Zhao +4 位作者 Jiayi Guo Huimin Cui Yiting Wang Xiong Luo Shixue Zheng 《Journal of Environmental Sciences》 2025年第10期660-670,共11页
Microbial selenite(Se(Ⅳ)) reduction to elemental selenium nanoparticles(SeNPs) and chromate(Cr(Ⅵ)) remediation constitute effective detoxification processes. The strain Bacillus wiedmannii ES2-45 can efficiently red... Microbial selenite(Se(Ⅳ)) reduction to elemental selenium nanoparticles(SeNPs) and chromate(Cr(Ⅵ)) remediation constitute effective detoxification processes. The strain Bacillus wiedmannii ES2-45 can efficiently reduce 5 mmol/L Se(Ⅳ) into SeNPs over 14 h and 1 mmol/L Cr(Ⅵ) within 36 h. Proteomic analysis and qRT-PCR revealed that reductases, including dithiol oxidoreductase(DsbA), Fe-S biosynthesis domain-containing protein(Fes),and aldose-6-phosphate reductase(Aldo), and bacillithiol(BSH) were involved in Se(Ⅳ) reduction. Heterologous expression further confirmed the Se(Ⅳ)-reducing function of three genes and enhanced the Se(Ⅳ) and Cr(Ⅵ) resistance ability. Moreover, the difference between Se(Ⅳ) treatments and controls both intra-and extra-cellular BSH concentration per biomass indicated that BSH contributes to Se(Ⅳ) reduction. Selenium-fortified rice was obtained by foliar spray of SeNPs synthesized by the strain ES2-45. To the best of our knowledge, DsbA and Aldo reductase were firstly verified for the role in Se(Ⅳ) reduction and Cr(Ⅵ)resistance. Importantly, it is a promising strategy that B. wiedmannii ES2-45 is served as an efficient bacterium for SeNP synthesis, selenium biofortification and heavy metal bioremediation. 展开更多
关键词 SeNP synthesis PROTEOME Selenite reductase CHROMATE Bacillithiol Foliar spray
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Advancing Acer phenology monitoring:fine-grained identification and analysis by deep learning RESformer
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作者 Weipeng Jing Huiming Xu +3 位作者 Weitao Zou Wenjun Zhang Chao Li Juntao Gu 《Journal of Forestry Research》 2025年第4期55-66,共12页
Climate change is a global phenomenon that has profound impacts on ecological dynamics and biodiversity,shaping the interactions between species and their environment.To gain a deeper understanding of the mechanisms d... Climate change is a global phenomenon that has profound impacts on ecological dynamics and biodiversity,shaping the interactions between species and their environment.To gain a deeper understanding of the mechanisms driving climate change,phenological monitoring is essential.Traditional methods of defining phenological phases often rely on fixed thresholds.However,with the development of technology,deep learning-based classification models are now able to more accurately delineate phenological phases from images,enabling phenological monitoring.Despite the significant advancements these models have made in phenological monitoring,they still face challenges in fully capturing the complexity of biotic-environmental interactions,which can limit the fine-grained accuracy of phenological phase identification.To address this,we propose a novel deep learning model,RESformer,designed to monitor tree phenology at a fine-grained level using PhenoCam images.RESformer features a lightweight structure,making it suitable for deployment in resource-constrained environments.It incorporates a dual-branch routing mechanism that considers both global and local information,thereby improving the accuracy of phenological monitoring.To validate the effectiveness of RESformer,we conducted a case study involving 82,118 images taken over two years from four different locations in Wisconsin,focusing on the phenology of Acer.The images were classified into seven distinct phenological stages,with RESformer achieving an overall monitoring accuracy of 96.02%.Furthermore,we compared RESformer with a phenological monitoring approach based on the Green Chromatic Coordinate(GCC)index and ten popular classification models.The results showed that RESformer excelled in fine-grained monitoring,effectively capturing and identifying changes in phenological stages.This finding not only provides strong support for monitoring the phenology of Acer species but also offers valuable insights for understanding ecological trends and developing more effective ecosystem conservation and management strategies. 展开更多
关键词 Fine-grained phenological period Acer phenological monitoring Green chromatic coordinate PhenoCam
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Adaptive Dispersion Estimation for Linearized Electronic Dispersion Compensation in IM-DD Systems
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作者 Huo Jiahao Tao Jianlong +3 位作者 Zhang Xiaoying Zhu Jin Qin Peng Wei Huangfu 《China Communications》 2025年第4期55-64,共10页
An adaptive dispersion estimation(ADE)is proposed to compensate dispersion and estimate the transfer function of the fiber channel with GerchbergSaxton(G-S)algorithm,using the stochastic gradient descent(SGD)method in... An adaptive dispersion estimation(ADE)is proposed to compensate dispersion and estimate the transfer function of the fiber channel with GerchbergSaxton(G-S)algorithm,using the stochastic gradient descent(SGD)method in the intensity-modulation and direct-detection(IM-DD)system,improving the tolerance of the algorithm to chromatic dispersion(CD).In order to address the divergence arising from the perturbation in the amplitude of the received signal caused by the filtering effect of the non-ideal channels,a channel-compensation equalizer(CCE)derived from the back-to-back(BTB)scenario is employed at the transmitter to make the amplitude of the received signal depicting the CD effect more accurately.The simulation results demonstrate the essentiality of CCE for the convergence and performance improvement of the G-S algorithm.Results show that it supports 112Gb/s four-level pulse amplitude modulation(PAM4)over 100 km standard single-mode fiber(SSMF)transmission under the 7%forward error correction(FEC)threshold of 3.8E-3.Besides,ADE improves the tolerance to wavelength drift from about 4 nm to 42 nm,and there is a better tolerance for fiber distance perturbation,indicating the G-S algorithm and its derived algorithms with the ADE scheme exhibit superior robustness to the perturbation in the system. 展开更多
关键词 chromatic dispersion digital signal process intensity modulation and direct detection
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Effects of different processing methods on the quality of Polygonatum cyrtonema Hua 被引量:1
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作者 Xin-Ning Zhang Shuang-Hui Shi +13 位作者 Jun-Li Zhang Fan-Miao Kong Hai-Ting Zhu Si-Yuan Ma Yu-Feng Hu Ming-Rui Jiang Hui-Nan Wang Meng-Lin Wang Xiao-Tong Wei Jing-Qiu Zhang Nan Sun Meng-Yu Chen Qian-Qian Liu Ying-Zi Wang 《TMR Modern Herbal Medicine》 CAS 2024年第2期28-34,共7页
Background:In this study,we explored the effects of different processing methods on the quality of Polygonatum cyrtonema Hua(PC),and the role of Huangjiu in the processing procedure.Methods:The sensory characteristics... Background:In this study,we explored the effects of different processing methods on the quality of Polygonatum cyrtonema Hua(PC),and the role of Huangjiu in the processing procedure.Methods:The sensory characteristics of the crude product,steamed product,and wine-processed product of PC were described.The colorimeter was used to analyze the chromatic values of three different processed products on PC.At the same time,the contents of the water extract and alcohol extract were measured separately.The content of three different processing Polygonatum Polysaccharide(PCP)was determined using 0.2%anthrone-sulfuric acid.The correlation difference between the chromatic values and chemical composition of different PC products was analyzed using various analytical methods.Results:The surface colors gradually deepened,the sweetness increased,the viscosity strengthened,and the tongue-numbing sensation disappeared after PC processing.The contents of extract and L^(*) gradually decreased from the crude to the steamed to the wine-processed product,consistent with the pattern of surface color alteration.While,E^(*)ab gradually increased.The content of PCP was crude product>wine-processed product>steamed product.The results of multivariate statistical analysis showed that the samples processed for crude,steamed,and wine-processed product were clustered into three classes.The correlation analysis showed that L^(*)and E^(*)ab were highly significant positively correlated with the content of PCP,and a*was significantly negatively correlated with the content of PCP.Conclusion:The results showed that the wine-processed product had the best quality.The internal quality of the PC was correlated with its characteristics and chromatic value.In this study,we investigated the internal and external quality of three different products of PC in order to provide a reference for further research on the impact of different processing methods on PC quality,the standardization of PC processing,and the role of Huangjiu in the processing of PC. 展开更多
关键词 Polygonatum cyrtonema Hua different products chemical composition chromatic value CHARACTERISTICS
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E-Total Coloring of Complete Bipartite Graphs K_(5,n)(5≤n≤7 113)Which Are Vertex-Distinguished by Multiple Sets
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作者 GUO Yaqin CHEN Xiang'en 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2024年第5期412-418,共7页
In this study,using the method of contradiction and the pre-assignment of chromatic sets,we discuss the E-total coloring of complete bipartite graphs K_(5,n)(5≤n≤7 113) which are vertex-distinguished by multiple set... In this study,using the method of contradiction and the pre-assignment of chromatic sets,we discuss the E-total coloring of complete bipartite graphs K_(5,n)(5≤n≤7 113) which are vertex-distinguished by multiple sets.The vertex-distinguishing E-total chromatic numbers of this kind of graph are determined. 展开更多
关键词 complete bipartite graph E-total coloring E-total chromatic number multiple sets chromatic sets
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Relationships between blood chromium exposure and liver injury:Exploring the mediating role of systemic inflammation in a chromate-exposed population
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作者 Zekang Su Yali Zhang +8 位作者 Shiyi Hong Qiaojian Zhang Jiayu Xu Guiping Hu Xiaojun Zhu Fang Yuan Shanfa Yu Tianchen Wang Guang Jia 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2024年第9期224-234,共11页
Hexavalent chromium and its compounds are prevalent pollutants,especially in the work environment,pose a significant risk for multisystem toxicity and cancers.While it is known that chromium accumulation in the liver ... Hexavalent chromium and its compounds are prevalent pollutants,especially in the work environment,pose a significant risk for multisystem toxicity and cancers.While it is known that chromium accumulation in the liver can cause damage,the dose-response relationship between blood chromium(Cr)and liver injury,as well as the possible potential toxic mechanisms involved,remains poorly understood.To address this,we conducted a follow-up study of 590 visits from 305 participants to investigate the associations of blood Cr with biomarkers for liver injury,including serum alanine aminotransferase(ALT),aspartate aminotransferase(AST),total bilirubin(TBIL),and direct bilirubin(DBIL),and to evaluate the mediating effects of systemic inflammation.Platelet(PLT)and the platelet-to-lymphocyte ratio(PLR)were utilized as biomarkers of systemic inflammation.In the linear mixed-effects analyses,each 1-unit increase in blood Cr level was associated with estimated effect percentage increases of 0.82%(0.11%,1.53%)in TBIL,1.67%(0.06%,3.28%)in DBIL,0.73%(0.04%,1.43%)in ALT and 2.08%(0.29%,3.87%)in AST,respectively.Furthermore,PLT mediated 10.04%,11.35%,and 10.77%increases in TBIL,DBIL,and ALT levels induced by chromate,respectively.In addition,PLR mediated 8.26%and 15.58%of the association between blood Cr and TBIL or ALT.These findings shed light on the mechanisms underlying blood Cr-induced liver injury,which is partly due to worsening systemic inflammation. 展开更多
关键词 Blood chromate Liver injury Systemic inflammation Mediation analysis
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Improved isochronous mass spectrometry with tune measurement
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作者 Han-Yu Deng Yuan-Ming Xing +5 位作者 Xu Zhou Yu-Hu Zhang Xin-Liang Yan Jin-Yang Shi Ting Liao Meng Wang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第11期174-181,共8页
In conventional isochronous mass spectrometry(IMS)performed on a storage ring,the precision of mass measurements for short-lived nuclei depends on the accurate determination of the revolution times(T)of stored ions.Ho... In conventional isochronous mass spectrometry(IMS)performed on a storage ring,the precision of mass measurements for short-lived nuclei depends on the accurate determination of the revolution times(T)of stored ions.However,the resolution of T inevitably deteriorates due to the magnetic rigidity spread of the ions,limiting the mass-resolving power.In this study,we used the betatron tunes Q(the number of betatron oscillations per revolution)of the ions and established a correlation between T and Q.From this correlation,T was transformed to correspond to a fixed Q with higher resolution.Using these transformed T values,the masses of ^(63)Ge,^(65)As,^(67)Se,and ^(71)Kr agreed well with the mass values measured using the newly developed IMS(Bρ-IMS).We also studied the systematics of Coulomb displacement energies(CDEs)and found that anomalous staggering in CDEs was eliminated using new mass values.This method of T transformation is highly effective for conventional IMS equipped with a single time-of-flight detector. 展开更多
关键词 Isochronous Mass Spectrometry Storage ring TUNE Natural chromaticity Nuclear mass measurement
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Equitable Total Coloring of Fibonacci Graphs
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作者 Yong LI Chunling TONG +1 位作者 Senyuan SU Yanan SU 《Journal of Mathematical Research with Applications》 CSCD 2024年第2期143-151,共9页
The equitable total coloring of a graph G is a total coloring such that the numbers of elements in any two colors differ by at most one.The smallest number of colors needed for an equitable total coloring is called th... The equitable total coloring of a graph G is a total coloring such that the numbers of elements in any two colors differ by at most one.The smallest number of colors needed for an equitable total coloring is called the equitable total chromatic number.This paper contributes to the equitable total coloring of Fibonacci graphs F_(∆,n).We determine the equitable total chromatic numbers of F_(∆,n) for∆=3,4,5 and propose a conjecture on that for∆>=6. 展开更多
关键词 Fibonacci graph equitable total coloring equitable total chromatic number
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On r-Hued Coloring of Hypercubes
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作者 FENG Bowen XIONG Wei 《新疆大学学报(自然科学版中英文)》 CAS 2024年第6期651-656,686,共7页
For positive integers k and r,a(k,r)-coloring of graph G is a proper vertex k-coloring of G such that the neighbors of any vertex v∈V(G)receive at least min{d_(G)(v),r}different colors.The r-hued chromatic number of ... For positive integers k and r,a(k,r)-coloring of graph G is a proper vertex k-coloring of G such that the neighbors of any vertex v∈V(G)receive at least min{d_(G)(v),r}different colors.The r-hued chromatic number of G,denoted χ_(r)(G),is the smallest integer k such that G admits a(k,r)-coloring.Let Q_(n) be the n-dimensional hypercube.For any integers n and r with n≥2 and 2≤r≤5,we investigated the behavior of χ_(r)(Q_(n)),and determined the exact value of χ_(2)(Q_(n))and χ_(3)(Q_(n))for all positive integers n. 展开更多
关键词 HYPERCUBE COLORING r-hued chromatic number
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The Erdös-Faber-Lovász Conjecture for Gap-Restricted Hypergraphs
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作者 Zhimin Wang 《Engineering(科研)》 2024年第2期47-59,共13页
An edge coloring of hypergraph H is a function   such that  holds for any pair of intersecting edges . The minimum number of colors in edge colorings of H is called the chromatic index of H and is ... An edge coloring of hypergraph H is a function   such that  holds for any pair of intersecting edges . The minimum number of colors in edge colorings of H is called the chromatic index of H and is denoted by . Erdös, Faber and Lovász proposed a famous conjecture that  holds for any loopless linear hypergraph H with n vertices. In this paper, we show that  is true for gap-restricted hypergraphs. Our result extends a result of Alesandroni in 2021. 展开更多
关键词 Linear Hypergraph Chromatic Index Erdös-Faber-Lovász Conjecture Edge Cardinality
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Crystallization behaviors of bayerite from sodium chromate alkali solutions 被引量:2
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作者 魏广叶 曲景奎 +4 位作者 郑裕东 齐涛 郭强 韩冰冰 赵宏欣 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第10期3356-3365,共10页
In order to clean production of chromium compounds, it is a critical process to remove aluminates and utilize aluminum compounds from artificial chromate alkali solutions. The effects of Na2 Cr O4 on the neutralizatio... In order to clean production of chromium compounds, it is a critical process to remove aluminates and utilize aluminum compounds from artificial chromate alkali solutions. The effects of Na2 Cr O4 on the neutralization curve, Al(OH)3 precipitation efficiency and induction period of bayerite were investigated. The results indicate that the neutralization curve of the artificial chromate alkali solutions shows three distinct regions and its induction period is longer than that of pure sodium aluminate solutions at the same aluminum concentration. And the decreased temperature and volume fraction of CO2 enhance the particle size of bayerite β-Al(OH)3. Bayerite composed of agglomerates of rods and cone frustums was obtained from alkali metal chromate solutions with 28.5% CO2(volume fraction) at temperatures ranging from 50 °C to 70 °C. Coarse bayerite with particle size(d50) from 24.2 μm to 29.3 μm extremely has few impurities, which is suitable for comprehensive utilization. 展开更多
关键词 chromate alkali solutions BAYERITE CARBONIZATION CRYSTALLIZATION precipitation efficiency
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Preparation of potassium chromate by roasting of carbon ferrochrome 被引量:1
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作者 胡国荣 王家良 +3 位作者 彭忠东 杜柯 王伟刚 蒋庆来 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第3期966-972,共7页
The oxidizing roasting process of carbon ferrochrome to prepare potassium chromate in the presence of potassium carbonate and air was investigated. The effects of reaction temperature, reaction time, mole ratio of pot... The oxidizing roasting process of carbon ferrochrome to prepare potassium chromate in the presence of potassium carbonate and air was investigated. The effects of reaction temperature, reaction time, mole ratio of potassium carbonate to carbon ferrochrome were studied, and thermodynamics and kinetics were also discussed. It was observed that the reaction temperature and reaction time had a significant influence on the roasting reaction of carbon ferrochrome. The reaction mechanism changed greatly as the temperature varied. A two-stage roasting process was favorable for the roasting reaction, and a chromium recovery rate of 97.06% was obtained through this two-stage roasting method. The chromium residue yielded from this method was only 1/3 of the product. Moreover, the component of Fe in the residue was as high as 55.04%. Therefore, it can be easily recovered to produce sponge iron, realizing complete detoxication and zero-emission of chromium residue. 展开更多
关键词 carbon ferrochrome potassium chromate two-stage roasting chromium residue zero-emission
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Crystallization of gibbsite from synthetic chromate leaching solution in sub-molten salt process 被引量:1
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作者 张培育 魏广叶 +2 位作者 郭强 曲景奎 齐涛 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第8期2734-2743,共10页
For the clean and economical production of chromium compounds, it is crucial to remove aluminates from chromate alkali solutions and utilize aluminum-containing compounds. In this work, carbonization was used to remov... For the clean and economical production of chromium compounds, it is crucial to remove aluminates from chromate alkali solutions and utilize aluminum-containing compounds. In this work, carbonization was used to remove aluminates from a synthetic chromate leaching solution containing a high K2O/Al2O3 mole ratio. The influence of reaction temperature, carbonization time, flow rate of carbon dioxide, and seed ratio on the precipitation of Al was investigated. The optimal output was obtained under the following experimental conditions: a reaction temperature of 50 °C, a carbonization time of 100 min, a carbon dioxide flow rate of 0.1 L/min, and a seed ratio of 1.0. Gibbsite was obtained following carbonization. The structure and morphology of the gibbsite were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and laser particle size analyzer. The particle size distribution and morphology of the gibbsite were significantly influenced by the experimental conditions. The gibbsite had a mean particle size (d50) of 16.72μm. The thermal decomposition of the gibbsite was analyzed by XRD and the decomposition path was determined. The obtained coarseα-Al2O3 precipitate, which contains 0.08% Cr2O3 and 0.10% K2O, was suitable for subsequent utilization. 展开更多
关键词 GIBBSITE secondary nucleation CARBONIZATION chromate leaching solution
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DEVELOPMENT AND PRELIMINARY APPLICATION OF OBJECTIFYING SYSTEM FOR TCM COLOR INSPECTION 被引量:2
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作者 郑冬梅 戴振东 王鸿谟 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第4期395-403,共9页
An objectifying system for color inspections of traditional Chinese medicine (CITCM) is developed. The entire system includes two parts : The hardware and the software. The hardware is an image acquiring device und... An objectifying system for color inspections of traditional Chinese medicine (CITCM) is developed. The entire system includes two parts : The hardware and the software. The hardware is an image acquiring device under a standard lighting condition, and it mainly includes a xenon lamp with color temperature of 5 500 K as light source, an integrating sphere used for diffusing light and a high resolution CCD camera. The software is used for digital image processing, and the procedure is divided into three steps. Firstly the skin/non-skin classifi- cation is performed by utilizing the threshold in chrominance channels of the RGB color space. Secondly, the fa- cial features are localized by using the image segmentation and coordinates sorting. Finally, the facial special re- gion(SR) corresponding to five internal organs is achieved by utilizing masks designed to take advantage of mor- phology. Subsequently, the chromaticity is calculated. The system is tested by taking 83 samples of 30 young and 53 elderly people. The experiment shows that there is significant difference of all SRs between the young and the elderly, and the system has better performance for objectifying research of CITCM. 展开更多
关键词 color inspection special region integrating sphere image processing CHROMATICITY significant dif- ference
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Coloring of some integer distance graphs 被引量:1
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作者 许克祥 宋增民 《Journal of Southeast University(English Edition)》 EI CAS 2003年第4期418-422,共5页
An integer distance graph is a graph G(Z, D) with the integer set Z as vertexset, in which an edge joining two vertices u and v if and only if | u - v | ∈ D, where D is a setof natural numbers. Using a related theore... An integer distance graph is a graph G(Z, D) with the integer set Z as vertexset, in which an edge joining two vertices u and v if and only if | u - v | ∈ D, where D is a setof natural numbers. Using a related theorem in combinatorics and some conclusions known to us in thecoloring of the distance graph, the chromatic number _X(G) is determined in this paper that is ofthe distance graph G(Z, D) for some finite distance sets D containing {2, 3} with D = 4 andcontaining {2, 3, 5} with | D | = 5 by the method in which the combination of a few periodiccolorings. 展开更多
关键词 distance graph chromatic number COMBINATION
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联合颈部血管彩超及DSA评估动脉粥样斑块与脑梗死关联性的意义 被引量:9
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作者 方波 《中国实用医药》 2014年第9期4-6,共3页
目的探讨颈部血管彩超及DSA在动脉粥样硬化性脑梗死中的临床应用价值。方法以120例动脉粥样硬化性脑梗死患者为患者组,75例未发生脑梗死患者为对照组,经颈部血管彩超及DSA检查。结果二者颈动脉粥样斑块发生率差异有统计学意义,120例脑... 目的探讨颈部血管彩超及DSA在动脉粥样硬化性脑梗死中的临床应用价值。方法以120例动脉粥样硬化性脑梗死患者为患者组,75例未发生脑梗死患者为对照组,经颈部血管彩超及DSA检查。结果二者颈动脉粥样斑块发生率差异有统计学意义,120例脑梗死患者中,颈动脉及椎动脉粥样斑块发生率为81%,对照组仅有13%。颈动脉斑块最常见颈总动脉分叉处,其次为颈动脉颅内段,椎动脉以起始段多见,其次为基底动脉分布,多以病灶同侧多见,易形成血管狭窄及血流动力学改变。结论颈动脉粥样硬化与脑梗死的发病存在关联性:联合颈部血管彩超与DSA能早期准确发现颈动脉粥样硬化斑块及了解斑块的狭窄率,对预防或治疗脑梗死的发生有重要意义。 展开更多
关键词 颈部血管彩超 动脉粥样硬化性脑梗死 颈动脉狭窄 Double CAROTID CHROMATIC ultrasonic(DCCU)
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交换环的图论性质 被引量:1
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作者 王明生 《北京师范大学学报(自然科学版)》 CAS CSCD 北大核心 1998年第3期319-323,共5页
设R是一个交换环,研究了R的2种图结构.首先,设N表示R的幂零根,,把R的元素作为图的顶点,2个不同的顶点x和y有一边相连接,当且仅当或者,并且x,y中至少1个不是幂零元素,,则证明了下述结果:设R是交换环,使用如上图结构,X(R... 设R是一个交换环,研究了R的2种图结构.首先,设N表示R的幂零根,,把R的元素作为图的顶点,2个不同的顶点x和y有一边相连接,当且仅当或者,并且x,y中至少1个不是幂零元素,,则证明了下述结果:设R是交换环,使用如上图结构,X(R)<+∞当且仅当|R|<+∞,并且此时x(R)=clique(R).其次,把R的元素看作图的顶点,2个不同顶点x和y有边相连,当且仅当Annx+Anny=R.则证明了对交换诺特环R,X(R)<+∞,并猜测x(R)=clique(R). 展开更多
关键词 图的chromatic数 交换环 图论
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