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Green Dyeing of Silk Fabric with Turmeric Powder Using Tamarind Seed Coat as Mordant 认领
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作者 Priti Sarker A. K. M. Ayatullah Hosne Asif +2 位作者 Mahbubur Rahman Md. Mujahidul Islam Khan Hridom Rahman 《材料科学与化学工程(英文)》 2020年第2期65-80,共16页
The current study is aimed to explore the sustainable dyeing approach of silk fabric with turmeric powder using tannin as mordant extracted from tamarind seed coat. For that, tamarind seed coat tannin was extracted an... The current study is aimed to explore the sustainable dyeing approach of silk fabric with turmeric powder using tannin as mordant extracted from tamarind seed coat. For that, tamarind seed coat tannin was extracted and applied as natural mordant alone and in combination with metal mordant namely copper sulphate for dyeing silk fabric with the extract of turmeric powder. Dyeing parameters such as temperature, time and mordant concentration were varying for optimizing the process. The color strength, color coordinates, color fastness to wash, perspiration, water and rubbing were evaluated for examining dyeing performance. Firstly, tannin was extracted from tamarind seed coat and applying on the silk fabric at 95&#176;C temperature for 45 min by varying concentration. Among them 15 g/l shows better results. Some samples were mordanted with both 15 g/l extracted tannin and 0.5% copper sulphate solution. The mordanted samples were dyed with turmeric dye by varying the time and temperature. By analyzing the test results, the sample mordanted with extracted tannin showed high color strength and good fastness properties dyeing at 80&#176;C for 60 min. The application of 0.5% copper sulphate mordant enhanced sustainable wash fastness properties. 展开更多
关键词 Tamarind SEED POWDER TANNIN Natural MORDANT Turmeric POWDER SILK
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文章速递Movement Patterns of the Eastern Chipmunk (<i>Tamias striatus</i>) in Four Fragmented Landscapes of Prince Edward Island, Canada 认领
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作者 Sheldon B. Opps Leslie A. Cudmore Marina Silva-Opps 《生态学期刊(英文)》 2020年第10期688-715,共28页
The analysis of animal movement patterns can provide important information on animals’ responses to habitat features. In this study, the movement paths of eastern chipmunks (<em>Tamias striatus</em>) were... The analysis of animal movement patterns can provide important information on animals’ responses to habitat features. In this study, the movement paths of eastern chipmunks (<em>Tamias striatus</em>) were examined in four landscapes, with different levels of habitat fragmentation, using either fluorescent powdering or spool-and-line tracking. Descriptions of the tree and ground vegetation communities were performed in the vicinity of the trail to obtain information on habitat use and habitat selection. Several key movement variables were calculated, including the total path length, net distance, fractal dimension, and radius of gyration. Despite statistically significant differences in some of the movement metrics between the four landscapes, the overall movement patterns were generically the same for all of chipmunk paths examined in this study. The data were compared to trends expected based on random or correlated random walks, as well as Lévy-walk models. The mean squared net displacement did not support the correlated random walk predictions, except at smaller spatial scales, but overall demonstrated Lévy-like super diffusive behaviour. Lévy-like patterns were also confirmed from the move-length distributions that demonstrated truncated-tail power-law behaviour. Although this would suggest invariance of the movement patterns at all spatial scales studied, fractal analysis revealed at least two transitions in movement patterns at scales of around 2 and 5 m. The transition point at 2 m was negatively correlated with the density of small trees, while the transition at ~5 m was positively correlated with the spatial distribution of large trees. As the habitat-preference data showed that small trees are among the least preferred habitat component, while large trees were among the most preferred habitat, chipmunks are likely to alter their movement behaviour to avoid small trees, and attracted towards large trees possibly to avoid predators. Overall, we determined three principal domains of movement: at smaller spatio-temporal scales, foraging activities dominate and the movement is highly correlated but also random;at intermediate spatial scales, chipmunks may be moving to avoid predators, using different environmental cues, and the movement is more directed (but still influenced by vegetation patterns at intermediate scales);at larger spatio-temporal scales, the movement is dominated by long-range/long-term memory and homing to burrows and other key habitat features, such as food caches, drives more directed movement. The fact that scale-dependent movement mechanisms could give rise to LW patterns is consistent with recent studies. 展开更多
关键词 Fluorescent Powder Spool-and-Line Fractal Radius of Gyration Lévy Walk Correlated Random Walk Small Mammals Prince Edward Island
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文章速递Electrochemical Behavior of Alumix 321 PM and AA6061 Alloys in 3.5 wt% NaCl Solution by Electrochemical Impedance Spectroscopy Measurements 认领
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作者 George Jarjoura 《材料科学与化学工程(英文)》 2020年第10期42-49,共8页
Powder metallurgy (PM) is a very interesting metal manufacturing technique in the production of automotive components of a net or near net shape. In this research, the electrochemical corrosion behavior of a commercia... Powder metallurgy (PM) is a very interesting metal manufacturing technique in the production of automotive components of a net or near net shape. In this research, the electrochemical corrosion behavior of a commercially available aluminum powder alloy known as Alumix 321 was investigated and compared to wrought alloy AA6061 in 3.5 wt% NaCl solution using Electrochemical Impedance Spectroscopy Measurements (EIS). Alumix 321 alloy samples were prepared by pressing the powder at pressures ranging from 50 to 500 MPa and subsequently sintering them for 30 min at 630<span style="white-space:nowrap;">&#176;</span>C. It was found that the presence of pores and their morphology strongly affect the corrosion behavior the PM samples. 展开更多
关键词 Aluminum Powder Metallurgy Aluminum Alloys Corrosion Electrochemical Impedance Spectroscopy AA6061 Alumix 321
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文章速递Determination of Levels of Asbestos Fiber in Cosmetic and Non-Cosmetic Products Sold within Enugu Metropolis—Enugu State, Nigeria 认领
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作者 Onyeka Okeke Harold Chinedu Okeke +2 位作者 Ernest Ezeh Charles Chukwubuikem Aniobi Uchechi Rowland Imoh 《环境保护(英文)》 2020年第10期862-871,共10页
Studies were carried out to determine asbestos fiber levels in cosmetic (talc powder) and non-cosmetic (gauze pad, plastic filler and ceiling tiles) products sold in market outlets within Enugu, metropolis, Enugu Stat... Studies were carried out to determine asbestos fiber levels in cosmetic (talc powder) and non-cosmetic (gauze pad, plastic filler and ceiling tiles) products sold in market outlets within Enugu, metropolis, Enugu State, Nigeria, using standard established procedures. The samples were pretreated based on its physical make-up and the asbestos fiber levels determined using scanning electron microscopy (SEM) with energy dispersing spectroscopy techniques. The mean range of asbestos fiber was, 0.02 - 0.06;0.01 - 0.05;0.01 - 0.04 and 0.03 - 0.06 f/cc for talc powder, gauze pads, plastic filler and ceiling tile samples respectively. The mean levels of asbestos fibers in the studied samples were within the recommended permissible limits. The samples contain asbestos fiber in the following decreasing order: ceiling tiles > talc powders > gauze pads > plastic fillers. Asbestos fiber was found present in the investigated local and foreign items sold in market outlets within the metropolis. This study shows that despite the ban on the use of asbestos in the industry in the manufacture of items meant for human use, its enforcement appears weak and lethargic and this could portend health danger especially in the use of produced items with high asbestos fiber friability such as talc powder. 展开更多
关键词 Asbestos Fiber Talc Powder Plastic Filler Ceiling Tile and Gauze Pad
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Diet Chocolates and Replacement of Cocoa Powder with Jackfruit Seed Powder 认领
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作者 Akshaya Ravindran Maya Raman +3 位作者 Ninisha Babu Ammu Dinakaran T. V. Sankar T. K. Srinivasa Gopal 《食品与营养科学(英文)》 2020年第3期220-233,共14页
Chocolate is a very popular food product that is relished by millions of people for its unique, rich and sweet taste. The health benefits of chocolate are immense which is attributed to its high polyphenolic content. ... Chocolate is a very popular food product that is relished by millions of people for its unique, rich and sweet taste. The health benefits of chocolate are immense which is attributed to its high polyphenolic content. In the current study, the diet chocolates using natural and artificial sweeteners were developed. Also, the jackfruit seed powder after fermentation (anaerobic and aerobic) was used to replace cocoa powder by 10%. The physiochemical and glycemic index of the chocolates were analyzed. The physiochemical analysis of the chocolates indicated that substitution of jackfruit seed powder did not alter significantly the proximate composition. It was found out that the glycemic index and glycemic load of the chocolates were significantly lower than commercial milk chocolate, which makes it a suitable food product for diabetic and other groups. The samples were packed in pouches made of metallised polyester films laminated with polyethylene for storage studies. Instrumental textural studies were in concordance with sensory observation, indicating that the product remained stable for 3 months at room temperature (26&deg;C ± 2&deg;C). The color of the product remained similar throughout the storage period indicating stable structural and surface characteristics. Hence, the chocolates developed using natural and artificial sweeteners have low GI and will minimize the risk of several chronic diseases including diabetes and the use of jackfruit seed powder as a substitute for cocoa powder has not altered any of the characteristic features of chocolate. 展开更多
关键词 Diet CHOCOLATE STEVIA SUCRALOSE JACKFRUIT SEED POWDER Glycemic Index
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Reactivity of Recycled Glass Powder in a Cementitious Medium 认领
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作者 Monique Tohoue Tognonvi Arezki Tagnit-Hamou +2 位作者 Léon Koffi Konan Ablam Zidol Wilfried Cyrille N’Cho 《玻璃与陶瓷期刊(英文)》 2020年第3期29-44,共16页
The reactivity of the recycled glass powder (GP) in a cementitious medium has been studied over time by means of X-ray diffraction and thermal gravimetric analysis. Two different mixtures based on cement/glass powder ... The reactivity of the recycled glass powder (GP) in a cementitious medium has been studied over time by means of X-ray diffraction and thermal gravimetric analysis. Two different mixtures based on cement/glass powder (0 or 20 wt% GP) and lime/glass powder (70 wt% GP) were considered. Analysis revealed the coexistence of both hydration and pozzolanic reaction during the hardening of the mortars. At young age, the cement hydration would prevail over the pozzolanic one resulting in a decrease of physico-chemical </span></span><a name="_GoBack"></a><span><span><span style="font-family:"">and mechanical properties of the material due to the dilution effect. The pozzolanic reaction that predominates from 91 days, would induce the formation of supplementary C-S-H leading to improve the material properties. 展开更多
关键词 Glass Powder Pozzolanic Reaction Calcium Silicate Hydrate Thermal Analysis X-Ray Diffraction
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Characterization of nanoparticle mixed 316L powder for additive manufacturing 认领
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作者 Wengang Zhai Wei Zhou +1 位作者 Sharon Mui Ling Nai Jun Wei 《材料科学技术:英文版》 SCIE EI CAS CSCD 2020年第12期162-168,共7页
Nanoparticles reinforced steels have many advantaged mechanical properties.Additive manufacturing offers a new method for fabricating nanoparticles reinforced high performance metal components.In this work,we report t... Nanoparticles reinforced steels have many advantaged mechanical properties.Additive manufacturing offers a new method for fabricating nanoparticles reinforced high performance metal components.In this work,we report the application of low energy ball milling in mixing nanoparticles and micron 316 L powder.With this method,0.3 and 1.0 wt% Y2 O3 nanoparticles can be uniformly distributed on the surface of 316 L powder with the parameters of ball-to-powder ratio at 1:1,speed at 90 rpm and 7 h of mixing.The matrix 316 L powders remain spherical in shape after the mixing process.In the meantime,the effect of low energy ball milling and the addition of Y2 O3 nanoparticles on the powder characteristics(flowability,apparent density and tap density) are also studied.Results show that the process of low energy ball milling itself can slightly decrease the flowability and apparent density of the 316 L powder.The addition of 0.3 and 1.0 wt% Y2 O3 nanoparticles can also decrease the flowability,the tap density and the apparent density compared with the original 316 L powder.All of these changes result from the rough surface of the mixed powder produced by ball milling and the addition of Y2 O3 nanoparticles.The powder’s rough surface can increase the coefficient of friction of powders.The mixture of 316 L powder and Y2 O3 nanoparticles can be successfully used for selective laser melting(SLM).The relative density of SLM 316 L-Y2 O3 is measured at 99.5%.However,Y2 O3 agglomerations were observed which is due to the poor wettability between 316 L and Y2 O3. 展开更多
关键词 Powder mixing Powder characterization FLOWABILITY Apparent density Tap density Additive manufacturing
Effects of Direct Switching Dual Bronchodilators between Dry Powder and Soft Mist Inhalers in COPD Patients 认领
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作者 Taisuke Akamatsu Toshihiro Shirai +11 位作者 Hiromasa Nakayasu Kanami Tamura Toshihiro Masuda Shingo Takahashi Yuko Tanaka Hirofumi Watanabe Yutaro Kishimoto Kyohei Oishi Mika Saigusa Akito Yamamoto Satoru Morita Kazuhiro Asada 《呼吸病期刊(英文)》 2020年第1期11-19,共9页
Objective: Dual bronchodilation with long-acting muscarinic antagonist and long-acting β2-agonist combinations are available worldwide in COPD patients. However, the choice of agents remains under debate. We hypothes... Objective: Dual bronchodilation with long-acting muscarinic antagonist and long-acting β2-agonist combinations are available worldwide in COPD patients. However, the choice of agents remains under debate. We hypothesized that switching devices between dry powder and soft mist inhalers without a wash-out period to mimic clinical practice would improve clinical symptoms and lung function. The aim of this study was to examine the effects of switching between once-daily glycopyrronium/indacaterol (GLY/IND) or umeclidinium/vilanterol (UMEC/VI), dry powder inhalers, and tiotropium/olodaterol (TIO/OLO), a soft mist inhaler, in COPD patients. Methods: This was a prospective, open-label, 8-week, observational study with follow-up. Subjects included 57 COPD patients, who attended outpatient clinics at Shizuoka General Hospital for routine check-ups between February and December 2015, receiving GLY/IND (50/110 μg) or UMEC/VI (62.5/25 μg). After an 8-week run-in period, medications were switched to TIO/OLO (5/5 μg). Study outcomes included patient’s global rating (PGR), modified MRC (mMRC), COPD assessment test (CAT), and spirometric and forced oscillatory parameters after 8 weeks. PGR used in this study was a 7-point scale ranging from 1 to 7, with 4 in the middle. Patients who consented to switch from TIO/OLO to GLY/IND or UMEC/VI were followed-up thereafter. Results: In total, 53 patients completed the study (mean age, 75 years;48 males and 5 females;GOLD 1/2/3/4 = 19/27/6/1;mMRC 0/1/2/3/4 = 14/22/12/4/1;UMEC/VI 26, GLY/IND 27). PGR, mMRC, and CAT improved in 20 (38%), 9 (17%), and 15 patients (28%), respectively. Respiratory system resistance at 5 Hz (R5), 20 Hz (R20), and the difference between R5 and R20 (R5 - R20) significantly improved. In a follow-up of 16 patients after switching from TIO/OLO to UMEC/VI (9) or GLY/IND (7), PGR, mMRC, and CAT improved in 5 (31%), 3 (12%), and 4 patients (25%), respectively, and R20 significantly improved (p = 0.011). Conclusions: Switching dual bronchodilators between dry powd 展开更多
关键词 Device Dry Powder INHALER DUAL Bronchodilator SOFT MIST INHALER SWITCHING
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Evaluation of the Anti-Proliferative Effects of a Green Tea and <i>Capsicum</i>Powder Extract in Cancer Cell Lines 认领
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作者 Eleana Hatzidaki Maria Papadimitriou Ioannis Papasotiriou 《癌症治疗(英文)》 2020年第2期44-54,共11页
In recent years the use of natural supplements in order to prevent, treat or delay recurrence of cancer or reduce chemotherapy toxicity has attracted much?attention. One such supplement is Capsol-T which consists of d... In recent years the use of natural supplements in order to prevent, treat or delay recurrence of cancer or reduce chemotherapy toxicity has attracted much?attention. One such supplement is Capsol-T which consists of de-caffeinated green tea and chili pepper extracts. The aim of the study was the evaluation of Capsol-T effect on the proliferation of various cancer cell lines representing different cancer types. Cell lines that were used in the study were: DU145, LNCap,?MCF7, HCT116 and MOR. The effect of various concentrations and incubation times of Capsol-T on cell viability was determined using the MTT method. The results do not show a common anti-proliferative pattern in all cancer cells.?In some cell lines and certain concentrations cell growth was significantly decreased at 24 hr which became more evident at 48?hr. The role of Capsicum?powder in cancer is unclear since both cancer cell proliferation and growth arrest have been demonstrated. Green tea on the other hand was found to decrease certain drugs’ bioavailability. Our results suggest that an anti-proliferative?effect in certain types of cancer should not be generalized to other types as well.?Different concentrations also affect the net result often having opposite effects. Overall, caution should be taken when using natural supplements for their anti-cancer effects. 展开更多
关键词 Proliferation Cancer Green TEA CAPSICUM POWDER
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Black Powder in Sales Gas Pipelines: Sources and Technical Recommendations 认领
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作者 Faisal Saleh Al Wahedi Mohammed Hameed Saleh Zin Eddine Dadach 《世界工程和技术(英文)》 2020年第1期60-73,共14页
One of the most severe problems affecting the efficient operations of gas pipelines is corrosion caused by black powder. According to the literature, the primary source for the existence of black powder is condensed w... One of the most severe problems affecting the efficient operations of gas pipelines is corrosion caused by black powder. According to the literature, the primary source for the existence of black powder is condensed water. In this case study, the temperature (40°C) of the sales gas is much higher than its dew point (9.24°C). The water is therefore in vapor phase. It is then proposed to remove water vapor from the gas at the entrance of the plant using an adsorption process. The recommended technology is the Layered Bed Temperature-Swing Adsorption (LBTSA) with micro-channels with molecular sieve zeolite 4A and activated alumina as adsorbents. In the case of presence of aerosols that could condense water, it is suggested to utilize a RED (Rare Earth Drum) magnetic separator in order to remove black powder from the gaseous feed. 展开更多
关键词 Black Powder SALES Gas Pipelines Temperature SWING Adsorption Magnetic FILTRATION
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钛及钛合金粉末制备与近净成形研究进展 认领
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作者 陈刚 路新 +3 位作者 章林 秦明礼 郭志猛 曲选辉 《材料科学与工艺》 EI CAS CSCD 北大核心 2020年第3期98-108,共11页
钛及钛合金以其优异的性能,广泛应用于航空航天、能源化工、生物医疗等高端领域。粉末近净成形技术能够实现钛及钛合金的绿色、低成本和高性能精密制造,有助于进一步扩大其应用范围。本文从钛粉制备、成形技术、性能与应用方面,对目前... 钛及钛合金以其优异的性能,广泛应用于航空航天、能源化工、生物医疗等高端领域。粉末近净成形技术能够实现钛及钛合金的绿色、低成本和高性能精密制造,有助于进一步扩大其应用范围。本文从钛粉制备、成形技术、性能与应用方面,对目前钛及钛合金粉末近净成形技术取得的研究进展进行了简要论述,并根据各技术目前面临的问题,提出了未来的发展趋势。 展开更多
关键词 钛及钛合金 粉末 近净成形 粉末冶金 低成本
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文章速递Therapeutic Effect of Shenling Baizhu Powder on Primary Nephrotic Syndrome Featuring Damp Abundance Due to Splenic Asthenia 认领
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作者 Yingyuan QIN Youming XIONG +3 位作者 Zhimei CUI Xiaowei DENG Fengmao ZHAO Liping FENG 《药用植物研究:英文版》 CAS 2020年第5期76-79,共4页
[Objectives]To observe the clinical efficacy of Shenling Baizhu Powder in the treatment of primary nephrotic syndrome(PNS)featuring damp abundance due to splenic asthenia.[Methods]40 patients with PNS were randomly di... [Objectives]To observe the clinical efficacy of Shenling Baizhu Powder in the treatment of primary nephrotic syndrome(PNS)featuring damp abundance due to splenic asthenia.[Methods]40 patients with PNS were randomly divided into treatment group(n=19)and control group(n=21).In the treatment group and the control group,methylprednisolone tablets were taken orally and cytoxan(CTX)was given intravenously for treatment;in the treatment group,based on oral administration of methylprednisolone tablets and intravenous drip of cytoxan(CTX),oral administration of traditional Chinese medicine(addition and subtraction of Shenling Baizhu Powder)was added.Urine routine,24-hour urinary protein,renal function and serum albumin were re-examined after 4 weeks of treatment.[Results]The total effective rate of the treatment group was significantly higher than that of the control group(89.47%vs 61.90%,P<0.05).After treatment,both groups could effectively reduce the levels of 24-hour urinary protein(P<0.05),serum creatinine(P<0.05)and urea nitrogen(P<0.05),and increase the level of serum albumin(P<0.05),but the degree of improvement in the treatment group was significantly higher than that in the control group(P<0.05),and the difference was statistically significant(P<0.05).[Conclusions]Methylprednisolone combined with addition and subtraction of Shenling Baizhu Powder could effectively reduce urinary protein,improve edema symptoms,shorten the course of hormone use and reduce adverse reactions in the treatment of PNS featuring damp abundance due to splenic asthenia. 展开更多
关键词 Primary nephrotic syndrome(PNS) Damp abundance due to splenic asthenia Addition and subtraction of Shenling Baizhu Powder
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文章速递基于小料配料流场的除尘罩结构优化 认领
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作者 姜鹏 王中医 李勇 《橡胶工业》 CAS 北大核心 2020年第10期781-786,共6页
基于原有小粉料配料除尘罩(方形)模型,采用计算流体动力学(CFD)仿真方法获取罩体附近流场特征,结合目标参数实现除尘罩几何结构的尺寸优化。结果表明,除尘罩下沿加装长度正好覆盖其与粉尘收集容器间隙的水平挡板,除尘罩下沿与收集容器... 基于原有小粉料配料除尘罩(方形)模型,采用计算流体动力学(CFD)仿真方法获取罩体附近流场特征,结合目标参数实现除尘罩几何结构的尺寸优化。结果表明,除尘罩下沿加装长度正好覆盖其与粉尘收集容器间隙的水平挡板,除尘罩下沿与收集容器上沿的垂直间距缩小至40 mm,保持抽吸管道与罩体的接口尺寸不变时,除尘罩除尘效果最佳。 展开更多
关键词 粉料 流场 除尘罩 模型仿真 结构优化
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Early-age strength property improvement and stability analysis of unclassified tailing paste backfill materials 认领
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作者 Qian Zhou Juan-hong Liu +1 位作者 Ai-xiang Wu Hong-jiang Wang 《矿物冶金与材料学报:英文版》 SCIE EI CAS CSCD 2020年第9期1191-1202,共12页
High-density tailings,small cementitious materials,and additives are used for backfill materials with poor early compressive strength(ECS),which may greatly affect the mining and backfill cycle,to prepare paste backfi... High-density tailings,small cementitious materials,and additives are used for backfill materials with poor early compressive strength(ECS),which may greatly affect the mining and backfill cycle,to prepare paste backfill materials(PBMs)with a high ECS.The effects and mechanisms of different early strength agents on the property of PBM are investigated.The action mechanism of additives on the properties of PBM is also analyzed through X-ray diffraction,scanning electron microscope,and energy dispersive spectrometry.Results show that the effects of single-component additives 1,3,and 6 are better than those of the other additives,and their optimal dosages are 3wt%,1wt%,and 3wt%,respectively.The optimum multicomponent combinations are 1wt%of additive 1 and 1.5wt%of additive 6.The ECS of the paste with additive 10 increases to a greater extent than that of the other pastes because of the synergistic action of additive 1 with additive 6.The hydration product of Ca(OH)2 is consumed,and more C-S-H gels are generated with the addition of additives to paste.Tailings particles,ettringite crystals,and gels intertwined with one another form a dense net-like structure that fills the pores.This structure can significantly improve the ECS of PBM. 展开更多
关键词 paste backfill unclassified tailings binder powder early-age strength microstructure
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Preparation and characterization of neodymium hydroxide powder via the hydration method 认领
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作者 Hongxi Li Chenggong Xu Qishan Yang 《中国化学工程学报:英文版》 SCIE EI CAS CSCD 2020年第7期1973-1980,共8页
The preparation of Nd(OH)3 powder by the direct hydration method using Nd2O3 as a raw material was studied,and the effects of stirring mode,H2O and Nd2O3 molar ratio,stirring rate,and reaction time on temperature chan... The preparation of Nd(OH)3 powder by the direct hydration method using Nd2O3 as a raw material was studied,and the effects of stirring mode,H2O and Nd2O3 molar ratio,stirring rate,and reaction time on temperature change and conversion rate in a hydration system were analyzed.The reasonable process conditions for the direct hydration of Nd(OH)3 by Nd2O3 were then determined.Process,morphology,and structure were considered in the preparation of neodymium hydroxide powder,and its composition was investigated by X-ray powder diffraction,scanning electron microscopy,laser particle size analysis,thermogravimetric differential thermal analysis,and chemical analysis.It has been proved that the process is simple and feasible,in line with the concept of modern green chemistry,and the products also meet the market requirements. 展开更多
关键词 Hydration method Neodymium hydroxide Powder preparation Influencing factor Green chemical engineering
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Chlorination roasting-coupled water leaching process for potash recovery from waste mica scrap using dry marble sludge powder and sodium chloride 认领
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作者 Sandeep Kumar Jena Jogeshwar Sahu +2 位作者 Geetikamayee Padhy Swagatika Mohanty Ajit Dash 《矿物冶金与材料学报:英文版》 SCIE EI CAS CSCD 2020年第9期1203-1215,共13页
The present paper reports the effective utilization of marble sludge powder(MSP)for the recovery of potash values from waste mica scrap using chlorination roasting-water leaching method.Characterization studies indica... The present paper reports the effective utilization of marble sludge powder(MSP)for the recovery of potash values from waste mica scrap using chlorination roasting-water leaching method.Characterization studies indicated the presence of dolomite as the major mineral phase in MSP,whereas muscovite and quartz were observed in the mica sample.The acid leaching studies suggest a maximum of 22%potash recovery under conditions:4 M H2SO4 acid,particle size of~100μm,stirring speed of 600 r/min,leaching temperature of 75℃,and leaching time of 90 min.The chlorination roasting-water leaching process was adopted to achieve the lowest level of 80%-90%potash recovery.The optimum conditions for the recovery of~93%potash from mica(~8.6wt%K2O)requires 900℃ roasting temperature,30 min roasting time,and 1:1:0.75 mass ratio of mica:MSP:NaCl.The roasting temperature and amount of NaCl are found to be the most important factors for the recovery process.The reaction mechanism suggests the formation of different mineral phases,including sylvite(KCl),wollastonite,kyanite,and enstatite,during roasting,which were confirmed by X-ray diffraction(XRD)analyses and scanning electron microscopy(SEM)morphologies.The MSP-blended NaCl additive is more effective for potash recovery compared with the other reported commercial roasting additives. 展开更多
关键词 potash recovery mica scrap marble sludge powder chlorination roasting water leaching
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石油化工粉体物料静电危害分析及预防措施 认领
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作者 高鑫 《安全.健康和环境》 2020年第9期16-19,共4页
从分析静电放电形式入手,探讨了粉体料仓内及粉体包装作业过程的静电危害性。结合自建粉体料仓静电实验装置以及现场静电检测设备,分别模拟测试了聚丙烯(PP)粒料风送作业过程和聚酯切片(PET)包装过程物料静电特性,总结了典型化工粉体物... 从分析静电放电形式入手,探讨了粉体料仓内及粉体包装作业过程的静电危害性。结合自建粉体料仓静电实验装置以及现场静电检测设备,分别模拟测试了聚丙烯(PP)粒料风送作业过程和聚酯切片(PET)包装过程物料静电特性,总结了典型化工粉体物料输送与包装过程中静电放电的防控技术与一般措施。 展开更多
关键词 料仓 粉体 静电危害 静电衰减 荷质比 静电电位 静电安全
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News Digest 认领
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《日用化学品科学:英文版》 2020年第2期5-6,共2页
JNJ Seeks Help from the Third Party to Conduct 155 Test JNJ(Johnson and Johnson)announced that third parties’tests had indicated that its baby powder contained no asbestos.In the early time,the USA FDA used to find o... JNJ Seeks Help from the Third Party to Conduct 155 Test JNJ(Johnson and Johnson)announced that third parties’tests had indicated that its baby powder contained no asbestos.In the early time,the USA FDA used to find out a small quantity of asbestos,the carcinogen known to us all,in baby powder produced by JNJ,and JNJ withdrew about 33,000 bottles of baby powder for solving this problem.JNJ also showed that two third-party labs had used four different ways to conduct 155 tests targeting at one same sample with no asbestos to be detected out. 展开更多
关键词 problem. POWDER DIGEST
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Corrosion Behavior of Steel Fibers in Reactive Powder Concrete with High Volume of Mineral Admixtures 认领
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作者 杨海涛 刘娟红 +2 位作者 XUE Yanpeng ZHOU Yucheng JI Hongguang 《武汉理工大学学报:材料科学英文版》 SCIE EI CAS 2020年第3期541-550,共10页
The corrosion behavior and the effects of temperature on critical chloride content (Ccrit) of steel fibers in RPC were analyzed by a pH meter, ion chromatography, mercury intrusion porosimetry (MIP), and electrochemic... The corrosion behavior and the effects of temperature on critical chloride content (Ccrit) of steel fibers in RPC were analyzed by a pH meter, ion chromatography, mercury intrusion porosimetry (MIP), and electrochemical techniques. It was found that the suspension pH value, the chloride binding capacity, and the total porosity of RPC were lower than those of high-performance concrete (HPC). The pore structure of RPC mainly consisted of gel pores. The Ccrit values of steel fibers in RPC and HPC at 20 ℃ were 1% and 2%, respectively. When the temperature reached 50 ℃, the Ccrit value of steel fibers in HPC decreased significantly, whereas it remained unchanged in RPC. The corrosion rate of corroded fibers in both RPC and HPC started to decrease with the rise in temperature. 展开更多
关键词 CORROSION steel fibers CHLORIDE reactive powder concrete critical chloride content
23 MHz核磁测定聚乙烯密度的影响因素 认领
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作者 王会能 秦超 +3 位作者 孙晓燕 张立兰 张玉强 王如琪 《合成树脂及塑料》 CAS 北大核心 2020年第3期30-34,90,共6页
采用聚乙烯标准试样,将用密度梯度柱法测试的密度值与在共振频率为23 MHz的核磁共振波谱仪(简称23 MHz核磁)上测得的核磁共振时域信号建立标准曲线。以此标准曲线为准,在23 MHz核磁上研究了温度、试样量、预热时间、添加剂对聚乙烯密度... 采用聚乙烯标准试样,将用密度梯度柱法测试的密度值与在共振频率为23 MHz的核磁共振波谱仪(简称23 MHz核磁)上测得的核磁共振时域信号建立标准曲线。以此标准曲线为准,在23 MHz核磁上研究了温度、试样量、预热时间、添加剂对聚乙烯密度的影响。结果表明:23 MHz核磁的核磁管恒温温度对聚乙烯密度的影响最大;适宜的试样量为4.0~5.5 g;在干浴恒温器中预热60 min后的密度值基本稳定;粒料测定结果的整体离散程度小于粉料。 展开更多
关键词 聚乙烯 密度 核磁共振波谱仪 粉料 粒料 结晶度 预热温度
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