Experiment and Research on the Concentration of Refractory Molybdenite Ore by Flotation Column

As certain refractory molybdenum with degree high oxidation and high argillization, on the premise of molybdenum concntrate recovery rate, in order to increase tenor of molybdenum concntrate, we use cyclonic static micro-bubble flotation column as concentration equipment. We used two concentrate courses to replace flotation machine eight concentrate courses. It showed that, in the condition of same recovery rate, tenor of molybdenum concntrate was 26.16%, rising by 8%. Using processes of flotation machine eight concentrate courses - concentrate regrinding - flotation column two concentrate courses, tenor of molybdenum concntrate was 39.33% and the recovery rate was of 8%. The results showed that, by increasing the degree of monomer dissociation of molybdenum ores, cyclonic static micro-bubble flotation column has higher capability in recovering and selecting ores of -400 mm size fraction. The high argillization resulting from the regrinding and unsuppressed gangue minerals are the main factors affecting the tenor of ore concentrate.

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Applied Research of Cyclonic-Static Micro-Bubble Flotation Column on the Microfine Hematite Flotation

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.641-642.242 ◽

2013 ◽

Vol 641-642 ◽

pp. 242-245

Author(s):

Wei Zhi Wang ◽

Miao Miao Han ◽

Chun Guang Yang

Keyword(s):

Recovery Rate ◽

Applied Research ◽

High Grade ◽

Operation Condition ◽

Flotation Process ◽

Flotation Tailings ◽

Flotation Column ◽

Iron Mine ◽

Micro Bubble ◽

Concentrate Grade

According to the situation of high grade of flotation tailings in flotation process of SiJiYing Iron Mine, static-swirl micro-bubble flotation column was used in micro-fine hematite flotation tests. Tests on operation condition, reagent condition and flotation flowsheet were done. Compared with the flotation machine test, he final result was that concentrate grade was enhanced by 2.42%, recovery increased by 6.58%, and tailings grade was reduced by 2.01%,recovery rate reduced by 3.25%.Ideal beneficiation indexes were obtained.

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Experiment and Research on the Separation Process of High Ash and Difficult Floatable Fine Coal

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.113-116.1565 ◽

2010 ◽

Vol 113-116 ◽

pp. 1565-1571

Author(s):

Xia Hui Gui ◽

Jiong Tian Liu ◽

Xiu Xiang Tao ◽

Yi Jun Cao ◽

Yong Tian Wang

Keyword(s):

Separation Process ◽

Quality Characteristic ◽

Gangue Mineral ◽

Flotation Process ◽

Flotation Machine ◽

Flotation Column ◽

Fine Coal ◽

Accumulation Index ◽

Micro Bubble ◽

Separation Equipment

As for certain high ash and difficult floatable fine coal, the coal quality characteristic is the frangible and easyly-clayed main gangue mineral kaolinite, and the high content of fine-grade and intermediate density grade materials. In order to reduce tiny slimes pollution and to increase quality and recovery rate of concentrate, we used cyclonic-static micro-bubble flotation column and XFD-3 flotation machine to experiment on separation process. It probed into re-concentration after grinding rough refined coal, classified flotation process and selective agglomeration-flotation process these three technical processes. The comparison of flotation machine test result showed that, using the flotation column as separation equipment, process of re-concentration after grinding rough refined coal could obtain the best refined coal accumulation index. When medicaments dosage is kerosene 800 g/t, GF 300 g/t, and sodium hexametaphosphate 1500g/t, refined coal production rate of flotation column is 59.47% and ash content is 10.63%.

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Recent Rapid Climate Changes in Antarctic and their Influence on Low Diversity Ecosystems

Papers on Global Change IGBP ◽

10.2478/v10190-010-0002-6 ◽

2010 ◽

Vol 17 (1) ◽

pp. 17-30 ◽

Cited By ~ 1

Author(s):

Katarzyna J. Chwedorzewska

Keyword(s):

Environmental Variables ◽

Climate Changes ◽

Biological Significance ◽

Global Changes ◽

Factors Affecting ◽

Low Diversity ◽

Main Factors ◽

The Antarctic ◽

High Diversity ◽

Temperature Water

ABSTRACTThe geographic position, astronomic factors (e.g. the Earth’s maximum distance from the Sun during winter), ice cover and altitude are the main factors affecting the climate of the Antarctic, which is the coldest place on Earth. Parts of Antarctica are facing the most rapid rates of anthropogenic climate change currently seen on the planet. Climate changes are occurring throughout Antarctica, affecting three major groups of environmental variables of considerable biological significance: temperature, water, UV-B radiation.Low diversity ecosystems are expected to be more vulnerable to global changes than high diversity ecosystems

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Pitting Corrosion of Biomedical Titanium and Titanium Alloys: A Brief Review

Current Nanoscience ◽

10.2174/1573413716999201125221211 ◽

2020 ◽

Vol 16 ◽

Author(s):

Yu-Wei Cui ◽

Liang-Yu Chen ◽

Xin-Xin Liu

Keyword(s):

Corrosion Resistance ◽

Pitting Corrosion ◽

Potential Temperature ◽

Growth Stages ◽

Factors Affecting ◽

Ti Alloys ◽

Pitting Corrosion Resistance ◽

Superior Mechanical Properties ◽

Good Biocompatibility ◽

Main Factors

Abstract:: Thanks to their excellent corrosion resistance, superior mechanical properties and good biocompatibility, titanium (Ti) and Ti alloys are extensively applied in biomedical fields. Pitting corrosion is a critical consideration for the reliability of Ti and Ti alloys used in the human body. Therefore, this article focuses on the pitting corrosion of Ti and Ti alloys, which introduces the growth stages of pitting corrosion and its main influencing factors. Three stages, i.e. (1) breakdown of passive film, (1) metastable pitting, and (3) propagation of pitting, are roughly divided to introduce the pitting corrosion. As reviewed, corrosive environment, applied potential, temperature and alloy compositions are the main factors affecting the pitting corrosion of Ti and Ti alloys. Moreover, the pitting corrosion of different types Ti alloys are also reviewed to correlate the types of Ti alloys and the main factors of pitting corrosion. Roughly speaking, β-type Ti alloys have the best pitting corrosion resistance among the three types of Ti alloys.

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Measuring the Efficiency of Football Clubs Using Data Envelopment Analysis: Empirical Evidence From Spanish Professional Football

SAGE Open ◽

10.1177/2158244021989257 ◽

2021 ◽

Vol 11 (1) ◽

pp. 215824402198925

Author(s):

Isidoro Guzmán-Raja ◽

Manuela Guzmán-Raja

Keyword(s):

Data Envelopment Analysis ◽

High Efficiency ◽

Sport Performance ◽

Data Envelopment ◽

Professional Football ◽

Efficiency Measure ◽

Factors Affecting ◽

Football Clubs ◽

Main Factors ◽

Using Data

Professional football clubs have a special characteristic not shared by other types of companies: their sport performance (on the field) is important, in addition to their financial performance (off the field). The aim of this paper is to calculate an efficiency measure using a model that combines performance (sport and economic) based on data envelopment analysis (DEA). The main factors affecting teams’ efficiency levels are investigated using cluster analysis. For a sample of Spanish football clubs, the findings indicate that clubs achieved a relatively high efficiency level for the period studied, and that the oldest teams with the most assets had the highest efficiency scores. These results could help club managers to improve the performance of their teams.

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Enzymatic Process for Cystoseira barbata Valorization: Ethanol Production and Additional By-Products

Processes ◽

10.3390/pr9050741 ◽

2021 ◽

Vol 9 (5) ◽

pp. 741

Author(s):

Doinita-Roxana Cioroiu Tirpan ◽

Ancaelena Eliza Sterpu ◽

Claudia Irina Koncsag ◽

Alina Georgiana Ciufu ◽

Tănase Dobre

Keyword(s):

Ethanol Production ◽

Alcoholic Fermentation ◽

Ethanol Yield ◽

Product Yield ◽

Liquid Ratio ◽

Experimental Conditions ◽

Factors Affecting ◽

Cystoseira Barbata ◽

Main Factors ◽

Process Factors

The aim of this study is to evaluate the potential of dried Cystoseira barbata alga for ethanol production through alcoholic fermentation. The influence of the main factors affecting the fermentation are studied in the frame of a 23 factorial experimental plan. The main factors influencing the process are the fermentation temperature (t from 25 °C to 35 °C), the solid to liquid ratio (S/L from 0.040 g/g to 0.080 g/g), and the cellulase ratio (R from 8 U/g d.m to 16 U/g d.m.). The maximum volatile compounds yield of 0.2808 g/g d.m and ethanol yield of 0.0158 g/g d.m were favored by the following experimental conditions: process temperature of 35 °C, solid to liquid ratio of 0.0415, and enzyme ratio of 16 U/g d.m. A statistical model was used to correlate the product yield with the process factors. Additionally, 19 interesting bioactive compounds were found in the enzymatic hydrolysis and alcoholic fermentation broths which seem likely to maintain natural defence mechanisms against diseases and physical disorders.

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The role of serum β-trophin and endostatin in patients with polycystic ovary syndrome: Are they correlated?

BMC Women s Health ◽

10.1186/s12905-021-01198-4 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Wei Gong ◽

Aikmu Bilixzi ◽

Xinmei Wang ◽

Yanli Lu ◽

Li Wan ◽

...

Keyword(s):

Polycystic Ovary Syndrome ◽

Influencing Factors ◽

Polycystic Ovary ◽

Pearson Correlation ◽

Healthy Controls ◽

Newly Diagnosed ◽

Ovary Syndrome ◽

Factors Affecting ◽

Main Factors

Abstract Background It’s necessary to investigate the serum β-trophin and endostatin (ES) level and its influencing factors in patients with newly diagnosed polycystic ovary syndrome (PCOS). Methods Newly diagnosed PCOS patients treated in our hospital were selected, and healthy women who took physical examination during the same period as healthy controls. We detected and compared the related serum indicators between two groups, Pearson correlation were conducted to identify the factors associated with β-trophin and ES, and the influencing factors of β-trophin and ES were analyzed by logistic regression. Results A total of 62 PCOS patients and 65 healthy controls were included. The BMI, WHI, LH, FSH, TT, FAI, FBG, FINS, HOMA-IR, TC, TG, LDL, ES in PCOS patients were significantly higher than that of healthy controls, while the SHBG and HDL in PCOS patients were significantly lower than that of healthy controls (all p < 0.05). β-trophin was closely associated with BMI (r = 0.427), WHR (r = 0.504), FBG (r = 0.385), TG (r = 0.405) and LDL (r = 0.302, all p < 0.05), and ES was closely associated with BMI (r = 0.358), WHR (r = 0.421), FBG (r = 0.343), TC (r = 0.319), TG (r = 0.404, all p < 0.05). TG, BMI, WHR and FBG were the main factors affecting the serum β-trophin levels (all p < 0.05). FBG, TC and BMI were the main factors affecting the serum ES levels (all p < 0.05). The TG, β-trophin, ES level in PCOS patients with insulin resistance (IR) were significantly higher than that of those without IR (all p < 0.05). Conclusion Increased β-trophin is closely associated with increased ES in patients with PCOS, which may be the useful indicators for the management of PCOS.

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Laboratory Tests on Engineering Properties of Wind-Blown Sand

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.170-173.706 ◽

2012 ◽

Vol 170-173 ◽

pp. 706-709

Author(s):

Zhao Lin Jia ◽

Shu Wang Yan ◽

Zhi Liang Huo

Keyword(s):

Water Content ◽

Laboratory Tests ◽

Fine Sand ◽

Engineering Properties ◽

Grain Composition ◽

Factors Affecting ◽

Compaction Curve ◽

Main Factors ◽

Dry And Wet Conditions ◽

Compaction Properties

By means of laboratory tests and theoretical calculation, the physical, mechanical properties and compaction mechanism of the wind-blown sand are studied to deal with the problem of how to use the wind-blown sand as roadbed materials. It is revealed that water content doesn’t affect the compressibility and the shear strength of the wind-blown sand obviously and the wind-blown sand can be compacted both in dry and wet conditions. The compaction curve of the ordinary fine sand is consistent with that of wind-blown sand and the main factors affecting the compaction properties are the grain composition, water content and compaction work.

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