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LOCAL EQUILIBRIUM METHOD IN STUDYING PHASE DIAGRAM OF Mn-MnO SYSTEM
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《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1989年第9期210-212,共3页
A special method based on the local equilibrium principle has been introduced in the research of the phase diagram of Mn-MnO system.With this method,the problems of volatilization of Mn and the corrosion of Mn and MnO... A special method based on the local equilibrium principle has been introduced in the research of the phase diagram of Mn-MnO system.With this method,the problems of volatilization of Mn and the corrosion of Mn and MnO to refractory materials were prevented efficiently.The solubility of oxygen in Mn and the composition of the interface between MnO and Mn were determined.Partial phase diagram of Mn-MnO system were constructed according to pres- ent experimental results. 展开更多
关键词 local equilibrium method Mn-MnO system phase diagram
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New Method for the Calculation of Stable Phase Diagrams
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作者 李麟 L.Delaey +1 位作者 P.Wollants O.V.D.Biest 《Advances in Manufacturing》 SCIE CAS 1997年第1期75-78,共4页
Numerical methods commonly used for the calculating phase diagrams were listed. A new method to calculate stable phase diagrams was presented which possesse the advantages of both the New-ton Raphson method and the si... Numerical methods commonly used for the calculating phase diagrams were listed. A new method to calculate stable phase diagrams was presented which possesse the advantages of both the New-ton Raphson method and the simplex method. This method is suitable for the calculation of the stable equilibria in complicated systems. For example. calculated results in comparison with experimental results as well as the prediction of new systems were shown in the present work 展开更多
关键词 numerical method phase diagram calculation
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Method of Phase Diagrams for the Analysis of Seism-Acoustical Spatial-Time Monitoring Data in Oil Wells
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作者 Olga Hachay Oleg Khachay 《Open Journal of Geology》 2018年第9期874-882,共9页
Experimental and theoretical studies of the mechanisms of vibration stimulation of oil recovery in watered fields lead to the conclusion that resonance oscillations develop in fractured-block formations. These oscilla... Experimental and theoretical studies of the mechanisms of vibration stimulation of oil recovery in watered fields lead to the conclusion that resonance oscillations develop in fractured-block formations. These oscillations, caused by weak but long-lasting and frequency-stable influences, create the conditions for ultrasonic wave’s generation in the layers, which are capable of destroying thickened oil membranes in reservoir cracks. For fractured-porous reservoirs in the process of exploitation by the method of water high-pressure oil displacement, the possibility of intensifying ultrasonic vibrations can have an important technological significance. Even a very weak ultrasound can destroy, over a long period of time, the viscous oil membranes formed in the cracks between the blocks, which can be the reason for lowering the permeability of the layers and increasing the oil recovery. To describe these effects, it is necessary to consider the wave process in a hierarchically blocky environment and theoretically simulate the mechanism of the appearance of self-oscillations under the action of relaxation shear stresses. For the analysis of seism acoustic response in time on fixed intervals along the borehole an algorithm of phase diagrams of the state of many-phase medium is suggested. 展开更多
关键词 phase diagramS method of ANALYSIS SPACE-TIME Monitoring Data Oil WELLS State of the Two Component MEDIUM
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DETERMINATION OF THE PHASE BOUNDARY OF AI-Mg-Y ALLOY EQUILIBRIUM DIAGRAM IN THE Al-RICH CORNER BY X-RAY METHOD
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作者 龙骧 朱定华 +2 位作者 宋利珠 徐惠平 管清录 《Journal of Rare Earths》 SCIE EI CAS CSCD 1990年第3期228-230,共3页
关键词 AI In DETERMINATION OF THE phase BOUNDARY OF AI-Mg-Y ALLOY EQUILIBRIUM diagram IN THE Al-RICH CORNER BY X-RAY method Al
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Thermodynamic database of the phase diagrams in the Mg-Al-Zn-Y-Ce system 被引量:2
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作者 LIU Xingjun WANG Cuiping +2 位作者 WEN Mingzhong CHEN Xing PAN Fusheng 《Rare Metals》 SCIE EI CAS CSCD 2006年第5期441-447,共7页
The Mg-Al-Zn-Y-Ce system is one of the key systems for designing high-strength Mg alloys. The purpose of the present article is to develop a thermodynamic database for the Mg-Al-Zn-Y-Ce multicomponent system to design... The Mg-Al-Zn-Y-Ce system is one of the key systems for designing high-strength Mg alloys. The purpose of the present article is to develop a thermodynamic database for the Mg-Al-Zn-Y-Ce multicomponent system to design Mg alloys using the calculation of phase diagrams (CALPHAD) method, where the Gibbs energies of solution phases such as liquid, fcc, bcc, and hcp phases were described by the subregular solution model, whereas those of all the compounds were described by the sublattice model. The thermodynamic parameters describing Gibbs energies of the different phases in this database were evaluated by fitting the experimental data for phase equilibria and thermodynamic properties. On the basis of this database, a lot of information concerning stable and metastable phase equilibria of isothermal and vertical sections, molar fractions of constituent phases, the liquidus projection, etc., can be predicted. This database is expected to play an important role in the design of Mg alloys. 展开更多
关键词 thermodynamic database CALPHAD method phase diagram Mg-Al-Zn-Y-Ce system magnesium alloys
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The efficiency and accuracy of probability diagram, spatial statistic and fractal methods in the identification of shear zone gold mineralization: a case study of the Saqqez gold ore district,NW Iran 被引量:1
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作者 Mirmahdi Seyedrahimi-Niaraq Amin Hekmatnejad 《Acta Geochimica》 EI CAS CSCD 2021年第1期78-88,共11页
In this study,geochemical anomaly separation was carried out with methods based on the distribution model,which includes probability diagram(MPD),fractal(concentration-area technique),and U-statistic methods.The main ... In this study,geochemical anomaly separation was carried out with methods based on the distribution model,which includes probability diagram(MPD),fractal(concentration-area technique),and U-statistic methods.The main objective is to evaluate the efficiency and accuracy of the methods in separation of anomalies on the shear zone gold mineralization.For this purpose,samples were taken from the secondary lithogeochemical environment(stream sediment samples)on the gold mineralization in Saqqez,NW of Iran.Interpretation of the histograms and diagrams showed that the MPD is capable of identifying two phases of mineralization.The fractal method could separate only one phase of change based on the fractal dimension with high concentration areas of the Au element.The spatial analysis showed two mixed subpopulations after U=0 and another subpopulation with very high U values.The MPD analysis followed spatial analysis,which shows the detail of the variations.Six mineralized zones detected from local geochemical exploration results were used for validating the methods mentioned above.The MPD method was able to identify the anomalous areas higher than 90%,whereas the two other methods identified 60%(maximum)of the anomalous areas.The raw data without any estimation for the concentration was used by the MPD method using aminimum of calculations to determine the threshold values.Therefore,the MPD method is more robust than the other methods.The spatial analysis identified the detail soft hegeological and mineralization events that were affected in the study area.MPD is recommended as the best,and the spatial U-analysis is the next reliable method to be used.The fractal method could show more detail of the events and variations in the area with asymmetrical grid net and a higher density of sampling or at the detailed exploration stage. 展开更多
关键词 Shear zone gold deposit Modeling of probability diagram method Concentration-area fractal method U-spatial statistics method phases of efficiency and accuracy mineralization
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Phase Diagram of the System KCl-CsBr-CaBr_2
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作者 BAO Xin-hua, CHEN Hua-li, LU Wen-cong, YAN Li-cheng College of Sciences, Shanghai University, Shanghai 201800, China 《Advances in Manufacturing》 SCIE CAS 2000年第S1期183-185,共3页
A computer prediction for the regularities of formation of binary bromide system was made. The results indicate that CsBr-CaBf2 molten salt system is binary complex compound-forming system. The phase diagram of CSBr-C... A computer prediction for the regularities of formation of binary bromide system was made. The results indicate that CsBr-CaBf2 molten salt system is binary complex compound-forming system. The phase diagram of CSBr-CaBt2 system has been determined by visual polythermal method in order to prove the prediction. The phase diagrams of the quasibinary system KCl-CsBr, KCl-CaBr2 and the quasiternary system CsBr-CaBr2-KCl were determined by using visual polythermal method. The phase diagrams of CsBr-CaBr2 and KCl-CaBr2 show that the intermediate compound is formed. The results are in agreement with the computer prediction. Here, the various parts of the phase diagram of the quasiternary system CsBr-CaBr2-KCl were discussed. 展开更多
关键词 CsBr molten salt phase diagram visual polythermal method
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Magnetization and magnetic phase diagrams of a spin-1/2 ferrimagnetic diamond chain at low temperature
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作者 成泰民 李美霖 +4 位作者 成智睿 禹国梁 孙树生 葛崇员 张新欣 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第5期630-638,共9页
We used the Jordan-Wigner transform and the invariant eigenoperator method to study the magnetic phase diagram and the magnetization curve of the spin-1/2 alternating ferrimagnetic diamond chain in an external magneti... We used the Jordan-Wigner transform and the invariant eigenoperator method to study the magnetic phase diagram and the magnetization curve of the spin-1/2 alternating ferrimagnetic diamond chain in an external magnetic field at finite temperature.The magnetization versus external magnetic field curve exhibits a 1/3 magnetization plateau at absolute zero and finite temperatures,and the width of the 1/3 magnetization plateau was modulated by tuning the temperature and the exchange interactions.Three critical magnetic field intensities H_(CB),H_(CE)and H_(CS) were obtained,in which the H_(CB) and H_(CE)correspond to the appearance and disappearance of the 1/3 magnetization plateau,respectively,and the higher H_(CS) correspond to the appearance of fully polarized magnetization plateau of the system.The energies of elementary excitation hω_(σ,k)(σ=1,2,3)present the extrema of zero at the three critical magnetic fields at 0 K,i.e.,[hω_(3,k)(H_(CB)]_(min)=0,[hω_(2,k)(H_(CE)]_(max)=0 and[hω_(2,k)(H_(CS)]_(min)=0,and the magnetic phase diagram of magnetic field versus different exchange interactions at 0 K was established by the above relationships.According to the relationships between the system’s magnetization curve at finite temperatures and the critical magnetic field intensities,the magnetic field-temperature phase diagram was drawn.It was observed that if the magnetic phase diagram shows a three-phase critical point,which is intersected by the ferrimagnetic phase,the ferrimagnetic plateau phase,and the Luttinger liquid phase,the disappearance of the 1/3 magnetization plateau would inevitably occur.However,the 1/3 magnetization plateau would not disappear without the three-phase critical point.The appearance of the 1/3 magnetization plateau in the low temperature region is the macroscopic manifestations of quantum effect. 展开更多
关键词 invariant eigen-operator method Jordan-Wigner transformations critical magnetic field intensity magnetic phase diagrams
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Studies on the Refolding of Egg White Lysozyme Denatured by Urea Using "Phase Diagram" Method of Fluorescence
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作者 边六交 董发昕 +2 位作者 梁长利 杨晓燕 刘莉 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2007年第12期1896-1903,共8页
The refolding of reduced and non-reducing egg white lysozymes in a urea solution was studied by a "phase diagram" method of fluorescence. The result showed that in the refolding of the reduced egg white lysozyme, an... The refolding of reduced and non-reducing egg white lysozymes in a urea solution was studied by a "phase diagram" method of fluorescence. The result showed that in the refolding of the reduced egg white lysozyme, an intermediate state of an egg white lysozyme exists at the urea concentrations in a final renaturation solution being about 4.5 mol/L, their refolding follows a three-state model; while in the refolding of the non-reducing egg white lysozyme, two intermediate states exist at the urea concentrations being separately 4.0 and 2.5 mol/L, and their refolding follows a four-state model. Through the comparison between the unfolding and refolding of an egg white lysozyme in the urea solution, it was found that both of the refolding of reduced and non-reducing egg white lysozyme molecules was irreversible to their unfolding in the urea solution. Finally, a suggested refolding was separately presented for the reduced and non-reducing egg white lysozymes in the urea solution. 展开更多
关键词 egg white lysozyme "phase diagram" method of fluorescence REFOLDING UREA
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多级双水相萃取木瓜蛋白酶的研究
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作者 朱恒伟 白新鹏 +4 位作者 梁秋杨 钟泷彬 常会敏 陈运坤 乔振栓 《食品与发酵工业》 CAS CSCD 北大核心 2024年第4期152-156,共5页
使用双水相萃取大规模生产木瓜蛋白酶时,为获得较高的回收率,通常需要较高的萃取剂浓度和体积比,但这会导致目标物的纯度和浓度降低。该研究采用聚乙二醇和柠檬酸钠组成的双水相体系在多个离心管之间的转移来模拟工业上常用的多级错流... 使用双水相萃取大规模生产木瓜蛋白酶时,为获得较高的回收率,通常需要较高的萃取剂浓度和体积比,但这会导致目标物的纯度和浓度降低。该研究采用聚乙二醇和柠檬酸钠组成的双水相体系在多个离心管之间的转移来模拟工业上常用的多级错流萃取和多级逆流萃取过程,以分配系数、酶活性回收率为指标,采用McCabe Thiele图解法得到多级逆流双水相萃取的理论级数,结果表明,当相比为0.5,原料液下相的木瓜蛋白酶的初始质量浓度为0.20 mg/mL时,使用3级逆流双水相萃取木瓜蛋白酶的酶活性回收率达到了96.75%,同时设计出多级逆流双水相萃取木瓜蛋白酶的优化方案。 展开更多
关键词 木瓜蛋白酶 双水相体系 多级错流萃取 多级逆流萃取 McCabe Thiele图解法
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混合配体构筑的Cd(Ⅱ)配合物的合成及其荧光性质
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作者 王凯民 顾雄 +4 位作者 杨冲福 邓娜 叶艳青 周强 马钰璐 《中山大学学报(自然科学版)(中英文)》 CAS CSCD 北大核心 2024年第3期113-118,共6页
采用含N刚性配体4,4'-联吡啶(bpy)与两性离子配体4-羧基-1-(3-羧基苄基)吡啶-1-氯化物(H_(2)LCl)混合的模式,利用液相扩散法,在室温下与Cd^(2+)自组装构筑了一例结构新颖的配合物{[Cd_(2.5)(L)_(2)(bpy)_(2)Cl(NO_(3))(H_(2)O)_(3)]... 采用含N刚性配体4,4'-联吡啶(bpy)与两性离子配体4-羧基-1-(3-羧基苄基)吡啶-1-氯化物(H_(2)LCl)混合的模式,利用液相扩散法,在室温下与Cd^(2+)自组装构筑了一例结构新颖的配合物{[Cd_(2.5)(L)_(2)(bpy)_(2)Cl(NO_(3))(H_(2)O)_(3)]·(NO_(3))·2H_(2)O}。通过单晶X衍射、Hirshfeld表面与二维指纹图、粉末X射线衍射、热重及固体荧光对配合物的结构及性质进行了分析。研究表明,该配合物为[Cd(bpy)_(2)]对称棒状单元与两条平行环链结构组成的一维梯子形链。借助丰富的分子间相互作用(π…π堆积、O—H…O及C—H…O氢键)配合物的梯子形链平行互穿,相互堆积,最终形成稳定的三维超分子结构。此外,由于d10金属离子的存在,配合物在425~466 nm波长范围内显示出与配体H_(2)LCl相似但强度增强的浅绿色荧光,CIE色坐标为(0.2870,0.3346)。 展开更多
关键词 配合物 晶体结构 液相扩散 分子间相互作用 固体荧光
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炒制饮片焦栀子中4种多环芳烃测定及初步风险评估
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作者 王文婷 郭娅 +1 位作者 阳文武 万莉 《中南药学》 CAS 2024年第7期1895-1898,共4页
目的建立对炒制饮片焦栀子中4种多环芳烃含量测定方法,并利用单因子污染指数和综合污染指数对其进行风险评估。方法采用高效液相-荧光检测法测定焦栀子中苯并(α)蒽、䓛、苯并(b)荧蒽、苯并(α)芘4种多环芳烃的含量;采用单因子污染指数... 目的建立对炒制饮片焦栀子中4种多环芳烃含量测定方法,并利用单因子污染指数和综合污染指数对其进行风险评估。方法采用高效液相-荧光检测法测定焦栀子中苯并(α)蒽、䓛、苯并(b)荧蒽、苯并(α)芘4种多环芳烃的含量;采用单因子污染指数和综合污染指数对其风险进行评估。结果4种多环芳烃线性关系良好,相关系数r≥0.999,回收率在75.82%~81.83%,RSD≤2.5%。风险评估结果表明焦栀子中苯并(α)蒽、苯并(b)荧蒽和䓛的污染程度相当且较大,远高于苯并(α)芘。同时,综合污染指数>1的占比为69.57%,提示4种多环芳烃污染较为严重,表明焦栀子多环芳烃污染风险需要关注,需进一步加强其风险监测和风险评估。结论该方法可以用于焦栀子中4种多环芳烃的测定及其风险评估,为炒制饮片焦栀子的多环芳烃污染水平进行监测,为其安全风险预警及保障人民用药安全提供数据依据。 展开更多
关键词 焦栀子 三峡库区 高效液相-荧光检测法 多环芳烃 风险评估
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基于相图法的水电二阶切换系统动力学特性与振荡分析
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作者 薛安成 庄文彬 +3 位作者 熊鸿韬 王嘉伟 杨滢 刘晓博 《电力自动化设备》 EI CSCD 北大核心 2023年第4期78-83,113,共7页
高比例水电系统在大扰动下出现了死区、限幅作用的超低频频率振荡,其所对应的切换系统仍缺乏动力学特性分析。鉴于此,基于二阶切换系统动力学特性,结合相图法分析系统参数对其动力学特性的影响,揭示系统在不同扰动、阻尼下发生频率振荡... 高比例水电系统在大扰动下出现了死区、限幅作用的超低频频率振荡,其所对应的切换系统仍缺乏动力学特性分析。鉴于此,基于二阶切换系统动力学特性,结合相图法分析系统参数对其动力学特性的影响,揭示系统在不同扰动、阻尼下发生频率振荡的动力学机理。首先给出水电二阶切换系统描述,分析了系统的平衡点存在性。其次结合相图法分析不同运行条件下系统的动力学特性,证明了相关极限环的存在性。最后分析了系统的非光滑分岔特性。结果表明:当平衡点正阻尼、系统调节区域负阻尼时存在1个稳定极限环,对应严重大扰动下的频率振荡;当平衡点负阻尼、系统有限幅时存在2个稳定极限环,分别对应一般、严重大扰动下的频率振荡,且二者振荡频率较为接近。 展开更多
关键词 切换系统 相图法 频率振荡 极限环 非光滑分岔
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基于最不利塔顶位移相图法的风电塔筒动力屈曲研究
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作者 李万润 范科友 杜永峰 《振动与冲击》 EI CSCD 北大核心 2023年第23期8-20,共13页
风电结构作为一种高耸的薄壁结构,易发生动力屈曲破坏,而我国的风电结构大多都不可避免地建于地震易发区。以西北地区某2.5 MW风力发电机为原型,对风-震耦合作用下风电塔筒的动力屈曲行为开展研究:基于谐波叠加法、叶素动量理论及尾流... 风电结构作为一种高耸的薄壁结构,易发生动力屈曲破坏,而我国的风电结构大多都不可避免地建于地震易发区。以西北地区某2.5 MW风力发电机为原型,对风-震耦合作用下风电塔筒的动力屈曲行为开展研究:基于谐波叠加法、叶素动量理论及尾流模型计算运转工况下风电结构所受风荷载;建立风电结构的有限元模型,探讨输入角度对于风电塔筒在风、地震及风-震耦合作用下的动力响应的影响;结合增量动力分析,提出基于“最不利塔顶位移相图法”来研究风电塔筒在风-震耦合作用下的动力屈曲行为,并探讨其主导因素。研究结果表明:风-震耦合作用会导致风电塔筒在强度方面的额外需求;在确定门洞的朝向问题上应考虑风-震耦合作用的因素;风-震耦合作用下风电塔筒呈现局部的塑性动力屈曲现象,而基于“最不利塔顶位移相图法”可以很好地判别并分析风电塔筒的动力屈曲。 展开更多
关键词 风电塔筒 动力屈曲 风-震耦合 增量动力分析(IDA) 相图法
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光甘草定-烟酰胺纳米乳的制备与抗氧化效果 被引量:3
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作者 鲁妍 聂琴 +2 位作者 赵海燕 黄婷婷 王少兵 《中南民族大学学报(自然科学版)》 CAS 北大核心 2023年第5期620-626,共7页
制备光甘草定-烟酰胺纳米乳(G-N-NE)并初步评价其抗氧化效果.采用相转变乳化高压均质法制备G-N-NE,借助伪三元相图法联合Box-Behnken响应面设计法(BBD-RSM)筛选获得G-N-NE最佳处方并进行验证,通过DPPH·自由基清除率初步评价了G-N-N... 制备光甘草定-烟酰胺纳米乳(G-N-NE)并初步评价其抗氧化效果.采用相转变乳化高压均质法制备G-N-NE,借助伪三元相图法联合Box-Behnken响应面设计法(BBD-RSM)筛选获得G-N-NE最佳处方并进行验证,通过DPPH·自由基清除率初步评价了G-N-NE的抗氧化效果.结果表明:G-N-NE最佳处方为辛酸癸酸三酰甘油/肉豆蔻异丙酯/吐温80/无水乙醇/光甘草定/0.10%烟酰胺水溶液(3.97∶1.99∶18.54∶4.64∶0.10∶70.76),粒径为(88.41±0.19)nm,多分散指数PDI为(0.253±0.01),Zeta电位为(-7.79±0.12)mV,烟酰胺载药量与包封率分别为(5.42±0.04)%与(93.01±0.23)%,光甘草定的载药量与包封率分别为(6.82±0.06)%与(97.01±0.06)%,相比光甘草定-烟酰胺溶液和光甘草定纳米乳,G-N-NE对DPPH·自由基有更好的清除效果,说明G-N-NE性质稳定、包封率高,具有良好的抗氧化效果. 展开更多
关键词 纳米乳 伪三元相图 Box-Behnken响应面设计法 光甘草定 烟酰胺
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伪三元相图联合星点设计-响应面法优选鸦胆子油微乳处方 被引量:1
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作者 黄益穗 钟文嘉 刘灼波 《中国药业》 CAS 2023年第12期45-50,共6页
目的优选鸦胆子油微乳制备工艺。方法优选鸦胆子油微乳由油包水(W/O)型转变为水包油(O/W)型微乳相临界点的测定方法,并初筛微乳油相配比。绘制伪三元相图,筛选最优乳化剂、助乳化剂、油相组成和Km值。以鸦胆子油的用量(%)、Km为考察因素... 目的优选鸦胆子油微乳制备工艺。方法优选鸦胆子油微乳由油包水(W/O)型转变为水包油(O/W)型微乳相临界点的测定方法,并初筛微乳油相配比。绘制伪三元相图,筛选最优乳化剂、助乳化剂、油相组成和Km值。以鸦胆子油的用量(%)、Km为考察因素,以微乳的平均粒径(nm)和多分散系数(PDI)为评价指标,采用星点设计-响应面法优选制备工艺。分别从电镜观察、类型鉴别、高速离心(转速为5000 r/min)、室温静置(30 d和60 d)方面考察按最优工艺制备的鸦胆子油微乳的理化性质。结果与目测法相比,电导率-含水量曲线法测定临界点更精确,且微乳的平均粒径和PDI更小,体系更稳定。微乳最优制备工艺为鸦胆子油8.66%、油酸8.66%、聚氧乙烯氢化蓖麻油60.81%、无水乙醇21.87%、Km值为2.78,含水量为71.01%。该工艺下测得微乳的平均粒径为(14.22±0.25)nm,PDI为0.066±0.004。鸦胆子油微乳外观圆整,为O/W型,且稳定性良好。结论该优选工艺操作简便,结果稳定可靠,可为鸦胆子油微乳的工业化生产提供借鉴。 展开更多
关键词 鸦胆子油微乳 电导率-含水量曲线法 目测法 伪三元相图 星点设计-响应面法
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复杂混合粒群简谐振动离析动力学特性
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作者 乔金鹏 杨金硕 +6 位作者 薛冬 胡柯羽 董良 段晨龙 江海深 赵跃民 蔚文朋 《煤炭学报》 EI CAS CSCD 北大核心 2023年第12期4571-4585,共15页
混合粒群在振动作用下的离析分层为矿物颗粒的筛分分级提供了实现基础,颗粒形状特征及粒级结构是影响离析速率及结果的重要因素。基于离散元法数值模拟探究了单个(非)球形大颗粒在小颗粒群中离析动力学特性,研究了颗粒形状对其离析速率... 混合粒群在振动作用下的离析分层为矿物颗粒的筛分分级提供了实现基础,颗粒形状特征及粒级结构是影响离析速率及结果的重要因素。基于离散元法数值模拟探究了单个(非)球形大颗粒在小颗粒群中离析动力学特性,研究了颗粒形状对其离析速率的影响规律,分析了二元均匀混合粒群中形状与粒度之间的交互作用,揭示了多元混合粒群中离析速率及转动取向分布规律。试验结果表明:较强振动作用下,球形大颗粒离析速率随粒度比的增加呈现先增加后降低的非单调变化趋势,而非球形大颗粒离析速率显著高于球形大颗粒,主要原因是其颗粒底端延伸至孔隙率波动较大的深床层。此外,非球形大颗粒与球形大颗粒的离析速率差值随着振幅的增加同样呈现先升高后降低的变化趋势;当二元混合颗粒群中存在对流时,其离析速率明显高于无对流颗粒群的离析速率;二元混合料群中非球形大颗粒的离析速率与转动取向呈现“类高斯”分布特征,且非球形颗粒的形状与粒度对最终离析结果的影响存在竞争关系,导致球形大颗粒-非球形小颗粒床在小粒度比、低球形度条件下出现异常的“反巴西果”现象;此外,颗粒形状对离析速率的影响显著性高于粒级结构,增加中间粒级颗粒会减缓粒群的离析过程,而拓宽粒度分布范围同样也会造成离析速率下降。 展开更多
关键词 非球形颗粒 振动离析 离散元法 相图 分层
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塞来昔布自微乳的制备及体外溶出研究 被引量:1
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作者 杨雪华 毛楷凡 +2 位作者 刘正平 李大伟 张岱州 《食品与药品》 CAS 2023年第4期302-307,共6页
目的 将塞来昔布(CXB)制备成自微乳药物递送系统(SMEDDS),以提高CXB的溶解度和生物利用度。方法 通过伪三元相图的绘制和单纯形网格法优化筛选出CXB-SMEDDS的最佳处方,然后对制备的CXB-SMEDDS进行质量评价和体外溶出研究。结果 优化后的... 目的 将塞来昔布(CXB)制备成自微乳药物递送系统(SMEDDS),以提高CXB的溶解度和生物利用度。方法 通过伪三元相图的绘制和单纯形网格法优化筛选出CXB-SMEDDS的最佳处方,然后对制备的CXB-SMEDDS进行质量评价和体外溶出研究。结果 优化后的CXB-SMEDDS处方组成为中链甘油三酯(MCT)10%、聚氧乙烯35蓖麻油(ELP35)60%、丙三醇30%,其在室温下为无色透明溶液,载药量为标示量的(101.42±0.29)%,包封率为(98.05±0.18)%,乳化时间为(8.42±0.63)s,乳化后能形成略泛蓝光的乳液,乳液在微观上呈圆球形结构,大小较为均一,并通过粒度仪测得其粒径为(16.21±0.72)nm,电位为(-15.8±1.2)mV,聚合物多分散指数(PDI)为0.072±0.011。体外溶出试验结果显示,与CXB原料药相比,CXB-SMEDDS的溶出度大大提高。结论 CXB-SMEDDS制备工艺简单,质量稳定,能显著提高CXB的溶解度和体外溶出度。 展开更多
关键词 塞来昔布 自微乳 三元相图 单纯形网格法 体外溶出
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混凝土建筑物化阶段碳排放测算与减排路径研究
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作者 赵愈 刘陆 +1 位作者 孙杨 孙思园 《沈阳建筑大学学报(社会科学版)》 2023年第4期372-378,共7页
科技高速发展带来的环境问题日益严重,碳排放成为全球普遍关注的问题。中国相应提出“双碳”目标,建筑业作为国民经济支柱产业之一,有效测算其碳排放总量是实现碳减排的重要前提。研究将碳排放因子法与能值分析法相结合,提出了碳排放核... 科技高速发展带来的环境问题日益严重,碳排放成为全球普遍关注的问题。中国相应提出“双碳”目标,建筑业作为国民经济支柱产业之一,有效测算其碳排放总量是实现碳减排的重要前提。研究将碳排放因子法与能值分析法相结合,提出了碳排放核算模型EA-CEF,并应用于混凝土建筑物化阶段。将物化科学中相图表达引入混凝土建筑物化阶段碳排放驱动因素分析,构建了能值相图与评价指标体系,进一步评估建筑发展可持续性。案例分析结果显示:混凝土建筑物化阶段碳排放量位居前四依次为混凝土、水泥、钢、涂料;EA-CEF核算模型提高了传统碳排放量测算法的准确性,考虑了区域性、时效性以及可持续性,为建筑物化阶段碳减排路径的研究奠定了基础。 展开更多
关键词 碳排放因子法 能值分析 碳减排 相图
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山羊绒和绵羊毛混合物荧光PCR法测试研究 被引量:1
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作者 李典典 《针织工业》 北大核心 2023年第3期86-88,共3页
根据GB/T 36433—2018《纺织品山羊绒和绵羊毛的混合物DNA定量分析荧光PCR法》标准,通过试验计算得出羊绒和羊毛的扩增效率分别为95.26%和98.60%,并以此对方法中用到的引物、探针和扩增条件等进行进一步验证。此外,结合固相萃取技术,探... 根据GB/T 36433—2018《纺织品山羊绒和绵羊毛的混合物DNA定量分析荧光PCR法》标准,通过试验计算得出羊绒和羊毛的扩增效率分别为95.26%和98.60%,并以此对方法中用到的引物、探针和扩增条件等进行进一步验证。此外,结合固相萃取技术,探究常规不过柱法、常规过柱法和试剂盒法3种不同前处理方法对羊绒和羊毛混合物样品测试结果的影响。结果表明:常规不过柱法有局限性,仅适用于颜色较浅的样品;而常规过柱法和试剂盒法在测试颜色较深的样品方面有一定的优势,在定性和定量方面结果比较一致;这3种方法可以满足试验者的不同需求,进一步提高试验效率。 展开更多
关键词 羊绒 羊毛 纤维定量分析 荧光PCR法 固相萃取 扩增效率
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