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1.
Summary The effect of the addition of four commercial pectolytic preparations on the visual characteristics (colour and turbidity) of red wines has been evaluated. The effect of both clarifying and colour extracting enzymes and the effect of different doses used, were evaluated and compared. All the red wines treated enzymatically, independent of the type of enzyme and dose, present chromatic characteristics which can be considered better than those of the control wines. Also, those wines treated with enzymes had greater stability during 2 years storage in bottles, in particular the turbidity was better than untreated wines.  相似文献   
2.
钒冶炼焙烧添加剂选择研究   总被引:1,自引:0,他引:1  
对小型钒冶炼厂焙烧工艺所用添加剂进行改进的可能性进行了探讨,研究了几种常用添加剂的焙烧条件,分析比较了其性能,提出用NaCl-Na2CO3作焙烧添加剂替代NaCl可大幅度减少大气污染,提高冶钒转化率;且不改变工艺流程,无需设备投资,具有较好的经济效益和环境效益。  相似文献   
3.
The interactions of VOHPO4· 0.5H2O and (VO)2P2O7 with the ammoxidation feed and the single components such as ammonia, oxygen, water and component mixtures were studied in detail using XRD and temperature-programmed reaction spectroscopy. The aim of this work was to improve the knowledge of the formation of the active phases or active sites of the catalysts from their precursors under the condition of the ammoxidation reaction. Similar catalytic properties of various applied VPO materials were discussed in terms of the presence of similar structure elements (domains of adjacent edge-sharing VO6 octahedra-units and P-O-NH4 groups).  相似文献   
4.
深入研究了利于音频数字水印实现空间定位的技术思想,提出了一种在数字音频中嵌入水印信息后,实现对声源的空间定位算法,详细阐述了该算法的设计思想,并分别给出了音频数字水印的嵌入过程和数字水印的提取过程。  相似文献   
5.
A novel method of pellet calcification roasting-H_2 SO_4 leaching was proposed to efficiently separate and extract vanadium(V) from vanadium-titanium(V-Ti) magnetite concentrates.The leaching rate of V is as high as 88.98%,while the leaching rate of impurity iron is only 1.79%.Moreover,the leached pellets can be used as raw materials for blast furnace ironmaking after secondary roasting.X-ray photoelectron spectroscopy(XPS) and scanning electron microscopy with energy dispersive X-ray spectrometry(SEMEDS) analyses showed that V~(3+) was oxidized to V~(5+) after roasting at 1200℃,and V~(5+) was then leached by H_2 SO_4.X-ray diffraction(XRD) analyses and single factor experiment revealed a minimal amount of dissolved Fe_2 O_3 during H_2 SO_4 leaching.Therefore,a high separation degree of V and iron(Fe) from V-Ti magnetite concentrate was achieved through H_2 SO_4 leaching.Compared with the traditional roastingleaching process,this process can achieve a high selectivity of V and Fe,and has excellent prospects for industrial production.  相似文献   
6.
The extraction of TiO~(2+),VO~(2+),VO_2~+ and MoO_2~(2+)by HDEHP,HEHEHP and HDTMPP was studiedrespectively.The orders of extraction ability for the three extractant systems are as follows:for TiO~(2+),VO~(2+):HDEHP>HEHEHP>HDTMPP;for VO_2~+, MoO_2~(2+):HDEHP< HEHEHP< HDTMPP.The experimental results were discussed from the point of view of extractant structures.  相似文献   
7.
基于对AutoCAD的DXF文件格式的详细分析,充分利用多义线的表达简洁性优点,并结合冲压件自身特点,提出了冲压件几何信息获取的方法及程序框架,详细说明了几何信息库的创建方法,并进一步采用Delphi6.0语言编程,实现了冲压几何信息库的建立和几何信息自动提取。  相似文献   
8.
土壤有效磷测试方法浅析   总被引:2,自引:0,他引:2  
马慧珍 《山西化工》2002,22(2):44-45
对有效磷的两种测定方法进行比较,讨论了两种方法之间的相关性及相关系数,为土壤有效磷的测定寻求更省时,省力的测试方法。  相似文献   
9.
A novel multiwalled carbon nanotube (CNTs) supported vanadium catalyst was prepared. The structure of catalyst prepared was characterized by TEM, BET, FTIR, XRD and temperature-programmed desorption (TPD) methods. The results indicated that vanadium particles were highly dispersed on the wall of carbon nanotubes. The V2O5/CNT catalysts showed good activities in the SCR of NO with a temperature range of 373–523 K. The Lewis acid sites on the surface of V2O5/CNT are the active sites for the selective catalytic reduction (SCR) of NO with NH3 at low temperatures. It was suggested that the reaction path might involve the adsorbed NH3 species reacted with NO from gaseous phase and as well as the adsorbed NO2 species. The diameter of CNTs showed positive effect on the activities of the catalysts. Under the reaction conditions of 463 K, 0.1 Mpa, NH3/NO = 1, GHSV = 35,000 h−1, and V2O5 loading of 2.35 wt%, the outer diameter of CNTs of 60–100 nm, the NO conversion was 92%.  相似文献   
10.
蒋优才 《中国陶瓷》1997,33(6):29-32
本文通过钒的应用,阐述了金光釉和凹釉的形成机理。并说明了其在陶瓷釉料生产中所扮演的重要角色。  相似文献   
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