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951.
952.
V. A. Chanturia T. A. Ivanova E. V. Koporulina 《Mineral Processing and Extractive Metallurgy Review》2013,34(5):288-304
The paper explicates methods of the mineral surface coating by noble metals allowing to obtain samples with micro- and nanoparticles of Au and Pt, simulating natural objects. The purpose is to investigate the sorption and flotation properties of collectors. As a result we obtained the samples of pyrite, pyrrhotine, arsenopyrite, and quartz artificially enriched by micro-sized and nano-sized particles of noble metals. The coating of noble metals was carried out using the method of reducing adsorption from H2[PtCl6], H[AuCl4], Na2[PtCl6], and Na[AuCl4] solutions and the method of adsorption of nano-sized particles from Au and Pt sols. Depending on the conditions of the sulfides enrichment by noble metals and sizes of new formations of Au and Pt, we considered possible areas of application, methods of samples’ research, and reagents interaction with microparticles and nanoparticles of gold and platinum. A complex of research methods of reagents’ interaction with metals and flotation investigations of minerals and ores revealed the selective properties of new complexing collectors (perhydro-1,3,5-ditiazin-5-yl-methane (MTKH), sodium di(isobutyl)dithiophosphinate (DIF), 2-(ethylthio)ethylamine (ETEA)) due to their chemical interaction with gold and platinum. 相似文献
953.
董明传 《有色金属(选矿部分)》2018,(3):32-36
云南某含大量易浮硅矿物锌矿含锌4.84%,含硅达28.85%,是非常典型难处理的含硅锌矿。针对该矿石特点,进行了大量捕收剂的选择和易浮硅矿物抑制剂复配的试验研究,成功寻找到了适合该锌矿的捕收剂,并开发了抑制易浮硅矿物的SCA抑制剂,试验研究应用于生产,获得锌精矿含锌品位达52.17%,锌回收率91.40%,达到了较好的选矿指标。 相似文献
954.
Mineral carbonation (MC) has been extensively researched all over the world since it was found as a naturally exothermic process to permanently sequester CO2. In order to accelerate the natural process, various methods for carbonation of Mg-/Ca- silicate minerals have been studied. It has been found that the MC efficiency will increase with an increase in CO2 pressure, retention time, temperature, mass ratio of Mg/Ca to Si in minerals, specific surface area, and the slurry concentration in a specific range, and with the introduction of NaCl and NaHCO3 or carbonic anhydrase. However, there is still no successful industrial application because of high economic costs and slow reaction rate. It is not economic to exploit Mg-/Ca- silicate minerals deposits or tailings to sequester CO2 by the MC due to the cost of grinding and heat pre-treatment. In some cases, the whole sequestration process may result in more CO2 emissions than the sequestered CO2 due to the requirements of energy inputs. The process, however, may be profitable as a whole (with carbon credits). It is suggested to combine the MC with valuable metals recovery from ore deposits in order to reduce the cost of the MC by cost sharing for mineral recovery. 相似文献
955.
Gara Luis Carmen Rubio Dailos González‐Weller Angel J. Gutiérrez Consuelo Revert Arturo Hardisson 《International Journal of Food Science & Technology》2011,46(4):774-780
Potatoes are a basic component of human diets worldwide being an excellent source of minerals linked the maintenance of health. Contents of calcium (Ca), magnesium (Mg), potassium (K), sodium (Na), cupper (Cu), iron (Fe), manganese (Mn), zinc (Zn), nickel (Ni) and chromium (Cr) in seventy‐four fresh potato samples from different varieties consumed in Tenerife Island (Canary Islands, Spain) were determined by flame atomic absorption spetrometry (FAAS). The mean concentrations were 60.1 mg kg?1, 222 mg kg?1, 5047 mg kg?1, 125 mg kg?1, 1.69 mg kg?1, 8 mg kg?1, 1.70 mg kg?1, 3.88 mg kg?1, 62.7 μg kg?1 and 19.9 μg kg?1 for Ca, Mg, K, Na, Cu, Fe, Mn, Zn, Ni and Cr, respectively. The varieties of local potatoes presented higher mineral contents than imported potatoes. Potassium presented the highest contents in all varieties of potatoes. Iron was the most abundant microelement. Local potatoes offer greater nutritional contributions to the recommended intakes than imported varieties. Within the macrominerals, the highest contribution to the intakes was observed for K, while Fe was the trace element with the largest contribution to the proposed intake. 相似文献
956.
Montserrat Gudiel‐Urbano Isabel Goi 《Journal of the science of food and agriculture》2002,82(8):913-917
The effect of fructooligosaccharide on protein digestibility and mineral absorption was studied in rats fed diets containing 5 g kg?1 fructooligosaccharide, 5 g kg?1 cellulose/fructooligosaccharide (1:1) or 5 g kg?1 cellulose as a source of dietary fibre. Addition of cellulose/fructooligosaccharide or fructooligosaccharide to the diet did not significantly modify the daily food intake and food efficiency. However, the fructooligosaccharide‐fed group showed a significant decrease in body weight gain compared with cellulose‐fed groups. Faecal excretion was significantly lower when there was fructooligosaccharide intake, despite there being no significant differences in cellulose‐fed groups. Intake of fructooligosaccharide produced an increase in caecal content and an enlargement of the caecal wall. This trophic effect could be attributed to short‐chain fatty acids produced from the anaerobic fermentation of fructooligosaccharide by intestinal bacteria. Cellulose/fructooligosaccharide enhanced the apparent absorption and apparent retention of Ca, Mg, Zn and Fe. Fructooligosaccharide‐fed rats experienced an increase in apparent absorption and apparent retention of Mg compared with cellulose‐fed rats. Fructooligosaccharide intake at the lowest dose was enough to provide a desirable effect on mineral bioavailability in rats without any modification of nutritional parameters. © 2002 Society of Chemical Industry 相似文献
957.
Mung Bean: Technological and Nutritional Potential 总被引:1,自引:0,他引:1
P. K. Dahiya M. A. J. S. Van Boekel N. Khetarpaul R. B. Grewal M. J. R. Nout 《Critical reviews in food science and nutrition》2015,55(5):670-688
Mung bean (Vigna radiata (L.) R. Wilczek) has been intensively researched; scattered data are available on various properties. Data on physical, chemical, food processing, and nutritional properties were collected for whole mung bean grains and reviewed to assess the crop's potential as food and to set research priorities. Results show that mung bean is a rich source of protein (14.6–33.0 g/100 g) and iron (5.9–7.6 mg/100 g). Grain color is correlated with compounds like polyphenols and carotenoids, while grain hardness is associated with fiber content. Physical properties like grain dimensions, sphericity, porosity, bulk, and true density are related to moisture content. Anti-nutrients are phytic acid, tannins, hemagglutinins, and polyphenols. Reported nutrient contents vary greatly, the causes of which are not well understood. Grain size and color have been associated with different regions and were used by plant breeders for selection purposes. Analytical methods require more accuracy and precision to distinguish biological variation from analytical variation. Research on nutrient digestibility, food processing properties, and bioavailability is needed. Furthermore, the effects of storage and processing on nutrients and food processing properties are required to enable optimization of processing steps, for better mung bean food quality and process efficiency. 相似文献
958.
摘要:目的建立一种简单、高效、抗基质干扰能力强的样品前处理结合高效液相色谱法(high performance liquid chromatography, HPLC)测定保健食品-复合营养素补充剂中维生素B1(vitamin B1,VB1)含量的分析方法。方法选取基质复杂的多种维生素矿物质片作为代表样品,通过创新性的设计酸性饱和乙二胺四乙酸二钠盐(ethylenediaminetetraacetic acid disodium salt,EDTA)提取溶液结合超声提取前处理方法,充分络合各类矿物质元素并有效消除其他基质干扰,针对样品中的维生素B1进行高效率提取。提取液经滤膜过滤后,HPLC分离检测。结果此改进后的分析方法能够针对多种维生素矿物质片中维生素B1含量进行准确定量。维生素B1在浓度范围1.0237~204.7380 μg/mL内线性良好(r2=0.9999);实际样品加标回收率达98.59%;相对标准偏差(relative standard deviation, RSD)为0.61%(n=6);方法定量限(limits of quantification, LOQ)为0.05 μg/mL。结论本方法简单、高效、抗基质干扰能力强、重现性好,适用于多种维生素矿物质片中的维生素B1的含量测定,同时也为复杂基质的保健食品-复合营养素补充剂中维生素B1的含量检测提供新的途径。 相似文献
959.
通过对神木长焰煤和青海肥煤不同粒度解离度及其在电选机上分选行为的研究,得出不同原料煤在同一粒度的解离度不同,其差异主要是由于煤中矿物杂质的嵌布特性引起的。在电选机上的分选试验结果表明:静电分选对0.3~0.15 mm和0.15~0.074 mm粒级煤的分选效果比较令人满意,可以有效脱除煤中矿物杂质,对煤炭产品深加工具有重要意义。 相似文献
960.
速冻蔬菜矿物质成分变化规律的研究 总被引:1,自引:0,他引:1
用原了吸收分光光度计法分析测定了菜椒、绿菜花、菠菜、芹菜等几种蔬菜在速冻加工与冷藏过程中营养元素的变化及变化规律。实验结果表明,在加工过程中的热烫处理使铁元素损失较大,钙、锌略有损失。在冷藏过程中这儿种元素均无明显变化。 相似文献