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清水混凝土用Ⅰ级低钙粉煤灰中浮黑物质分析
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作者 姜骞 王强 +1 位作者 于诚 徐文 《新型建筑材料》 2022年第4期52-55,93,共5页
粉煤灰浮黑现象极易造成清水混凝土外观色差,通过宏观和微观测试方法对比分析了Ⅰ级低钙粉煤灰及其浮黑物质的物理化学性质。结果表明:粉煤灰中浮黑物质的主要组成元素为Al、Si和O,与粉煤灰相比其主要组成晶相中莫来石更多、石英较少,... 粉煤灰浮黑现象极易造成清水混凝土外观色差,通过宏观和微观测试方法对比分析了Ⅰ级低钙粉煤灰及其浮黑物质的物理化学性质。结果表明:粉煤灰中浮黑物质的主要组成元素为Al、Si和O,与粉煤灰相比其主要组成晶相中莫来石更多、石英较少,浮黑物质的颗粒尺寸(中位粒径D_(50)=85μm)明显大于粉煤灰(中位粒径D_(50)=13μm);浮黑物质的组成与热性质均表明其并非粉煤灰中未燃尽碳,利用烧失量指标不能准确评价浮黑物质含量。 展开更多
关键词 级低钙粉煤灰 黑物质 物理化学性质 清水混凝土 色差
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小麦黑胚病籽粒黑变物质的理化性质分析 被引量:1
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作者 李巧云 姜玉梅 +3 位作者 徐凯歌 李梦钰 王丝雨 吴青桐 《麦类作物学报》 CAS CSCD 北大核心 2020年第6期707-713,共7页
黑胚病是危害小麦生产的重要籽粒病害。为了解小麦黑胚病症状产生的原因,用碱溶酸沉的方法提取感黑胚病籽粒黑变部位的物质(黑变物质)与健康籽粒相同部位提取物(BPF)以及致病菌麦根腐平脐蠕孢(Bipolaris sorokiniana)的胞内黑色素与胞... 黑胚病是危害小麦生产的重要籽粒病害。为了解小麦黑胚病症状产生的原因,用碱溶酸沉的方法提取感黑胚病籽粒黑变部位的物质(黑变物质)与健康籽粒相同部位提取物(BPF)以及致病菌麦根腐平脐蠕孢(Bipolaris sorokiniana)的胞内黑色素与胞外黑色素,并对其进行紫外-可见吸收光谱、红外光谱扫描以及光、热稳定性等理化性质分析。结果显示:(1)病粒黑变物质的紫外吸收峰(235 nm)与B.sorokiniana的胞外、胞内黑色素的紫外吸收峰不一致(210 nm),而与BPF的紫外吸收峰相同;(2)病粒黑变物质与BPF的红外光谱一致,而与B.sorokiniana的胞外、胞内黑色素不一致;(3)病粒黑变物质与BPF的光、热稳定性较差,而来源于B.sorokiniana的胞内、胞外黑色素相对稳定。综上所述,黑胚病籽粒的黑变物质与致病菌B.sorokiniana的黑色素的理化性质有较大差异,而与健康粒相同部位提取物的理化性质类似,推测该物质是由小麦籽粒本身合成,而不是来源于病原真菌。 展开更多
关键词 小麦 胚病 物质 紫外-可见吸收光谱 红外光谱
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燃煤机组改烧生物质黑颗粒燃料的适用性研究
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作者 王克 陈艺 +1 位作者 刘重阳 汤陈怀 《能源工程》 2021年第6期8-14,共7页
生物质黑颗粒燃料特性与常规的煤燃料的特性差别较大,当将燃煤机组改烧生物质黑颗粒燃料时,需对锅炉本体及各个系统进行相应的适用性评估。以410 t/h燃煤机组为研究对象,开展燃煤机组改烧黑颗粒改造的适用性研究,通过对热力校核计算评... 生物质黑颗粒燃料特性与常规的煤燃料的特性差别较大,当将燃煤机组改烧生物质黑颗粒燃料时,需对锅炉本体及各个系统进行相应的适用性评估。以410 t/h燃煤机组为研究对象,开展燃煤机组改烧黑颗粒改造的适用性研究,通过对热力校核计算评估、受热面安全性评估以及超低排放系统、制粉系统、除灰渣系统等评估研究分析,为实现燃煤机组与生物质黑颗粒燃料燃烧的良好匹配奠定基础,可为其他类型的机组改燃生物质黑颗粒燃料提供借鉴。 展开更多
关键词 物质颗粒 燃煤机组 适用性 改烧
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连云港黑碳气溶胶污染特征研究 被引量:10
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作者 陈程 花艳 +1 位作者 王瑜 杨伟波 《环境监控与预警》 2018年第2期45-48,共4页
采用2016年大气多参数站监测数据,分析连云港市大气中ρ(黑碳气溶胶)的小时及月度变化规律,结果表明,观测期间,黑碳气溶胶与NO_2、CO、PM_(10)、PM_(2.5)显著相关,与风速、能见度等呈负相关;黑碳气溶胶年均值为2.10μg/m^3,日变化呈明... 采用2016年大气多参数站监测数据,分析连云港市大气中ρ(黑碳气溶胶)的小时及月度变化规律,结果表明,观测期间,黑碳气溶胶与NO_2、CO、PM_(10)、PM_(2.5)显著相关,与风速、能见度等呈负相关;黑碳气溶胶年均值为2.10μg/m^3,日变化呈明显双峰型,峰值出现在08:00和21:00左右;从季节看,ρ(黑碳气溶胶)冬春季高、夏秋季低;在不利气象条件时,ρ(黑碳气溶胶)有所增高,通过模型分析化石燃料燃烧产生的黑碳占比增大,说明在不利气象条件时,化石燃料燃烧产生的黑碳是影响ρ(黑碳气溶胶)及ρ(颗粒物)上升的主要因素。 展开更多
关键词 碳气溶胶 化石燃料燃烧产生的 物质燃烧产生的 污染特征 相关性 连云港
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美拉德反应及其产物抗氧化活性研究进展 被引量:19
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作者 严昊 付惠 谢冰 《宜宾学院学报》 2007年第12期82-84,共3页
美拉德反应主要指还原糖与氨基酸、蛋白质之间的复杂反应,它与食品加工、疾病生理过程等有重要关系。本文综述了美拉德反应产物抗氧化活性及其国内外的研究进展,并对其抗氧化机理进行探讨。
关键词 美拉德反应 精类物质 抗氧化活性
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镁合金压铸件表面缺陷机理分析
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作者 侯利锋 卫英慧 +3 位作者 阴国盛 胡兰青 郭跃文 许并社 《电子显微学报》 CAS CSCD 北大核心 2003年第6期633-633,共1页
关键词 镁合金压铸件 表面缺陷 机理分析 加工性能 比强度 表面磷化工艺 表面处理 耐蚀性 絮状物质 表面质量
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Equation of State for Neutralino Star as a Form of Cold Dark Matter
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作者 REN Jie LI Xue-Qian SHEN Hong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第1期212-216,共5页
In order to study the structure of neutralino star and dark galaxy, we consider dynamical interactions due to boson-exchange in the neutralino matter. Taking into account interactions of neutralinos with bosons, we de... In order to study the structure of neutralino star and dark galaxy, we consider dynamical interactions due to boson-exchange in the neutralino matter. Taking into account interactions of neutralinos with bosons, we derive the equation of state (EOS) of neutralino stars in terms of the relativistic mean-field approach. Then we apply the resulting EOS to investigate properties of the neutralino star such as its density profile and mass limit. For example, if the neutralino mass is around 1 TeV, the Oppenheimer mass limit of the neutralino star is obtained as 6.06 ×10^-7 M⊙, and the corresponding radius is about 7.8 mm. Actually, due to an increasing annihilation rate as indicated by our calculation, this dense state can never be realized in practice. Our results also show that the low-density neutralino star may be a possible aggregation of the cold dark matter. 展开更多
关键词 neutralino star equation of state dark matter
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Charge coupled devices (CCD) photometry and long-term optical variability of gamma-ray-loud BL Lacertae object Mkn 421 被引量:3
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作者 张雄 郑永刚 +2 位作者 张皓晶 胡绍明 谢照华 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第9期2185-2192,共8页
Evidence for the long-term optical curve variability and colour behaviour of the BL Lac object Mkn 421 is presented. Our results show that the amplitude of the optical variations of Mkn 421 is only about △B=4.7 magni... Evidence for the long-term optical curve variability and colour behaviour of the BL Lac object Mkn 421 is presented. Our results show that the amplitude of the optical variations of Mkn 421 is only about △B=4.7 magnitude in the B-band for its photometric history from 1899 to 2002. The results of optical photometric monitoring of the Mkn 421 from April 2000 to Jan 2002 are provided. During our observation, Mkn 421 shows significant rapid variations and exhibits short time variability of 2.42 hours in the B band. A strong correlation between the B - V colour index and the magnitude in the B band is found. Our charge coupled device (CCD) photometry of Mkn 421 shows that the measured results are in good agreement with the predicted optical variability period of about 23 years. 展开更多
关键词 BL Lac object Mkn 421 PHOTOMETRY mass of central black hole colour index
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A Breakthrough in the Logical Deduction about the Cognition Theory
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作者 Dongkai Li 《Journal of Philosophy Study》 2015年第8期418-420,共3页
The contradiction would produce the power only in the condition that this contradiction stays within a substance. The movement power for the cognition is not produced by the contradiction between people's thinking an... The contradiction would produce the power only in the condition that this contradiction stays within a substance. The movement power for the cognition is not produced by the contradiction between people's thinking and the objective things, for the thinking and the objective things are not in a same substance, which is Hegel's problem. Then, where is the power for people's cognition from? This paper has a conclusion as this: The "Ego" and the "Nonego" are a pair of contradiction within a person's body. The cognition is a kind of people's movement. So, the cognition is the process moved by the power from the "Ego" and the "Nonego" of a person's body. 展开更多
关键词 CONTRADICTION COGNITION PEOPLE EGO Nonego
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The Hegelian Tragedy, Negative Dialectic and Ethical Substance in Sophocles' Antigone
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作者 Ying-shan CHEN 《Journal of Literature and Art Studies》 2018年第4期557-567,共11页
Breaking with Aristotle's theory of tragedy in which the grand magnitude of the spirit of the tragic hero somehow trapped and misguided by a certain tragic flaw arouses the audiences' emotional intensity of pity and... Breaking with Aristotle's theory of tragedy in which the grand magnitude of the spirit of the tragic hero somehow trapped and misguided by a certain tragic flaw arouses the audiences' emotional intensity of pity and fear for the functioning of catharsis, Hegel analyzes the structure of tragedy in terms of the social conflict, in the case of Sophocles' Antigone, between the ruler Creon and the rebel Antigone, the patriarchal state and the individual woman, the civil codes and the divine law. Rejecting Creon's dictatorship and performing civil disobedience, Antigone intentionally buries the dead body of her brother Polyneices at the cost of being sentenced to death. Through this sacrifice, Antigone exposes the structural fissure of the civil society embedded in decaying morality for realizing the higher ideal of divine law and ethics. Through Antigone's sacrifice, the paradox of self-denial and self-elevation manifests the inner principle of dialectic through which the very opposite forces of contradiction engender the dynamic facets of the formation of modern civil society. As Hegelian dialectic is driven by its inner principle of negativity or negation of negation, through self-denial, Antigone transcends the moral codes of the mundane world for reaching the higher divine will. Yet, this dialectical ascending does not indicate a transcendent hero beyond the human world; instead, through the means of self-denying sacrifice, Antigone accomplishes the purpose of the divine will and conveys the divine spirit incarnated in the human flesh. For Hegelian tragic hero, the external and internal conflicts lead to the realization of self-consciousness and the ultimate consummation of heroic identity. Instead of being conditioned by Aristotelian tragic flaw and unconquerable fate, for Hegel, Antigone explicates the modern rebellious spirit of free will, and this martyrdom, not in the sense of scapegoat as the passive substitute for the sin of collective human community, presents a modern sense of tragic hero, an incarnated flesh invested with politically radical spirit. The flesh figure of heroine Antigone exemplifies the immanent power of ethical substance and dialectically transforms the divine will into the earthly spirit. Thus, this paper aims to investigate into the shift from Aristotle's concept of tragic hero to Hegelian dialectic tragedy and further examines how Hegelian tragic hero engenders the historical move into Western modernity through negative dialectic and accomplishes the self-other positioning of ethical substance presented in Sophocles' Antigone. 展开更多
关键词 Sophocles' Antigone TRAGEDY Aristotle Hegel negative dialectic ethical substance
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西安地区PM_(2.5)中环境持久性自由基(EPFRs)性质及来源研究 被引量:5
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作者 孙浩堯 陈庆彩 +4 位作者 牟臻 王羽琴 沈振兴 张立欣 李艳广 《环境科学学报》 CAS CSCD 北大核心 2019年第1期197-203,共7页
环境持久性自由基(environmental persistent free radicals, EPFRs)是一种近年来备受关注的环境风险物质,可能会危害人体健康.本研究利用溶剂萃取方法从西安市大气PM_(2.5)样品中分离出物质,运用电子顺磁共振波谱(EPR)技术分析了不同... 环境持久性自由基(environmental persistent free radicals, EPFRs)是一种近年来备受关注的环境风险物质,可能会危害人体健康.本研究利用溶剂萃取方法从西安市大气PM_(2.5)样品中分离出物质,运用电子顺磁共振波谱(EPR)技术分析了不同大气污染状况下大气PM_(2.5)样品及类黑碳成分中EPFRs的种类和含量,并分别测定PM_(2.5)和类黑碳成分催化H_2O_2产生羟基自由基的能力.结果表明:PM_(2.5)中的EPFRs约有85%~90%是由类黑碳成分产生的.可见光照(400~700 nm)前后,PM_(2.5)样品中EPFRs的含量增加10%~20%.此外,实验结果亦表明PM_(2.5)中能催化H_2O_2产生羟基自由基的物质主要是PM_(2.5)中水溶性物质而不是类黑碳.大气PM_(2.5)中的EPFRs没有显著催化H_2O_2产生羟基自由基的能力,也不能将O_2分子转化为活性氧物质. 展开更多
关键词 物质 PM2.5 持久性自由基 羟基自由基
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Quasinormal Modes of a Black Hole with Quintessence-Like Matter and a Deficit Solid Angle for Electromagnetic Perturbation
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作者 王春艳 赵亚峰 高亚军 《Communications in Theoretical Physics》 SCIE CAS CSCD 2012年第6期1101-1104,共4页
We investigate the electromagnetic perturbation around a black hole with quintessence-like matter and a deficit solid angle.The complex frequencies of the quasinormal modes of electromagnetic perturbation are evaluate... We investigate the electromagnetic perturbation around a black hole with quintessence-like matter and a deficit solid angle.The complex frequencies of the quasinormal modes of electromagnetic perturbation are evaluated by the third-order WKB approximation.The results show that the electromagnetic perturbation around the black hole damps more slowly owing to the presence of the quintessence-like.The phenomenon can be distinguished from the black hole only with a deficit angle. 展开更多
关键词 electromagnetic perturbation quasinormal frequencies WKB approximation
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Information Loss for QCD Matter in AdS Black Holes at LHC
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作者 A.Sepehri M.E.Zomorrodian +1 位作者 S.Shoorvaz M.Hasheminia 《Communications in Theoretical Physics》 SCIE CAS CSCD 2013年第10期427-432,共6页
In this paper, we find the information loss for QCD matter in AdS black holes at LHC by extending the Gottesman and Preski11 methode to AdS black holes. We calculate the information transformation from the collapsing ... In this paper, we find the information loss for QCD matter in AdS black holes at LHC by extending the Gottesman and Preski11 methode to AdS black holes. We calculate the information transformation from the collapsing matter to the state of outgoing Hawking radiation for both quarks and gluons. It is noticed that for finite values of quark and gluon energies, information from all emission processes experiences some degrees of loss. Possible explanation for this feature will be presented in this paper. 展开更多
关键词 information loss blacl HOLE
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Thermodynamic behavior for generalized f(R) gravity with arbitrary coupling between matter and geometry
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作者 WU YaBo ZHAO YueYue +3 位作者 LU JianBo ZHANG Xin TONG HaiDan YANG Hao 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2012年第12期2331-2337,共7页
The thermodynamic behavior of field equations for the generalized f(R) gravity with arbitrary coupling between matter and geometry is studied in the two kinds of spacetime,i.e.,the both spatially homogenous,isotropic ... The thermodynamic behavior of field equations for the generalized f(R) gravity with arbitrary coupling between matter and geometry is studied in the two kinds of spacetime,i.e.,the both spatially homogenous,isotropic FRW universe and static,spherically symmetric black hole spacetime.The field equations of the generalized f(R) gravity with arbitrary coupling between matter and geometry can be cast to the form of the first law of thermodynamics with the reputed entropy production terms dS,which are quite general and can degenerate to the cases of Einstein's general relativity and pure f(R) gravity with non-coupling and nonminimal coupling as special cases.The appearance of the entropy production term dS illustrates that the horizon thermodynamics is non-equilibrium one for the generalized f(R) gravity with arbitrary coupling between matter and geometry. 展开更多
关键词 f(R) gravity THERMODYNAMICS black hole FRW universe
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Using DGT to Assess Cadmium Bioavailability to Ryegrass as Influenced by Soil Properties 被引量:1
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作者 SONG Ningning WANG Fangli +1 位作者 MA Yibing TANG Shirong 《Pedosphere》 SCIE CAS CSCD 2015年第6期825-833,共9页
A generally accepted method for predicting the bioavailability and transfer of cadmium(Cd) from soil to plants has not yet been established. In this study, the diffusive gradients in thin films(DGT) and conventional e... A generally accepted method for predicting the bioavailability and transfer of cadmium(Cd) from soil to plants has not yet been established. In this study, the diffusive gradients in thin films(DGT) and conventional extraction methods for metal fractions were used to investigate how effective these methods were at predicting Cd bioavailability to ryegrass(Lolium perenne) and to assess whether these holistic variables were independent of the soil property variables. The influences of soil properties on the predictive capabilities of the different methods were evaluated using multivariate statistics. The Cd concentrations in the shoots and roots of ryegrass correlated more closely with the effective Cd concentration measured by DGT(CE), compared with those with soil total Cd, pore water Cd, and ethylenediaminetetraacetic acid disodium salt(Na2EDTA)- and acetic acid(HOAc)-extractable Cd. When soil properties were included in a stepwise multiple linear regression, Cd transfer to L. perenne was negatively influenced by p H and positively influenced by organic matter(OM). The multivariate statistics showed that the adjusted correlation coefficients for the plots involving soil total Cd, pore water Cd, and Na2EDTA- and HOAc-extractable Cd had been significantly improved after considering the influences of soil properties, which suggested that these methods were p H and OM dependent. For CE, the relationship was p H independent or only dependent in strongly acidic soils. These results suggested that the main soil factors affecting bioavailability had the lowest impact on the DGT technique. Therefore, the DGT technique provided significant advantages over conventional methods when assessing Cd bioavailability. 展开更多
关键词 conventional extraction methods diffusive gradients in thin films effective Cd concentration organic matter pore water
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