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作者： (美)斯蒂芬·g. 霍夫曼(Stefan g. Hofmann)

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不锈钢粉末冶金过滤器的性质

稀有金属材料与工程 1977年第6期 42-58页

作者： g霍夫曼 D卡普尔张正德

对高多孔不锈钢过滤器材料的某些问题进行研究。金属粉末的类型和过滤器特性之间的相互关系。等静压的优点。提出了一种对过滤器特性没有影响的新的嵌镶作业。强调了测定过滤器性能标准试验方法的必要性。

关键词：孔隙度孔隙率粒级过滤器分离设备渗透性毛细管孔粉末颗粒抗剪强度试验不锈钢粉末

在淤泥土壤上经过十二年试验测定各种有机物质中腐殖质综合的形成系数和土壤中腐殖质含量的变化

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江西农业科技 1981年第5期 30-31页

作者： g·霍夫曼 M·万·鲁姆贝克周淮培

1950年,在比利时海边的围垦区,对土壤结构的退化进行了研究(德冷希尔DeLeenheer和德布得特De Boodt 1950),此后过了好些年,于1962年秋天开始作了一个长期的试验(一直延续到1974年),以研究机械化农业对土壤结构和物理性土壤肥力的影响。... 详细信息

1950年,在比利时海边的围垦区,对土壤结构的退化进行了研究(德冷希尔DeLeenheer和德布得特De Boodt 1950),此后过了好些年,于1962年秋天开始作了一个长期的试验(一直延续到1974年),以研究机械化农业对土壤结构和物理性土壤肥力的影响。发现,即使在淤泥地区(肥沃的地区)由于不施农家肥料和机械化农业使用重型机器,对于土壤结构的退化,也会产生严重的后果。

关键词：有机物质腐殖质土壤肥力经过淤泥碎屑沉积物

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基因如何界定美

环球科学 2024年第9期 84-91页

作者：唐纳德·霍夫曼唐璐(译) 不详

美是一种客观的属性么,如果不是,它又应该与什么直接相关?是一种经历数亿年演化逐渐形成的偏好吗?1757年,英国哲学家大卫·休谟(David Hume)在《趣味的标准》中指出,美存在于欣赏者的眼中。“美,”他说,“不是事物本身的特质:它仅存在... 详细信息

美是一种客观的属性么,如果不是,它又应该与什么直接相关?是一种经历数亿年演化逐渐形成的偏好吗?1757年,英国哲学家大卫·休谟(David Hume)在《趣味的标准》中指出,美存在于欣赏者的眼中。“美,”他说,“不是事物本身的特质:它仅存在于旁观者的头脑中;每个头脑感知到不同的美。”

关键词：旁观者大卫·休谟事物本身欣赏者

Effects of frothers on bubbles size and flotation performance of hydrophobic minerals

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Journal of Central South University 2024年第7期31卷 2280-2299页

作者： gülşah gÜVEN Berivan TUNÇ Ş.Beste AYDIN gülay BULUT Mineral Processing Engineering Department Faculty of MinesIstanbul Technical UniversityMaslak 34469IstanbulTurkey Research Center Metso OutotecKuparitie 1028101 PoriFinland

Frothers facilitate the reduction of bubbles size by preventing bubbles coalescence and produce more stable *** collision probability of the bubbles and particles substantially increases by decreasing bubble *** the same volume system,fewer bubbles result from a distribution of large-sized bubbles,and more bubbles result from a distribution of small-sized *** this research,fundamental two-phase frother characterization parameters were aimed to link with three-phase coal and talc flotation *** this purpose,the effect of single and dual frother systems on inhibiting bubble coalescence was investigated with methyl isobutyl carbinol(MIBC),isooctanol(2 ethyl hexanol),pine oil,and Dowfroth *** on the results of single frothers,isooctanol at the lowest critical coalescence concentration(CCC)value of 6×10^(−6) achieved the smallest bubbles with Sauter mean diameter of 0.80 *** blending Dowfroth 250 and pine oil,the bubbles size decreased significantly,reaching 0.45 *** the highest recoveries in coal flotation were obtained in single and frother blends where the bubbles size was measured as the smallest in two-phase system,and such a relationship was not found for talc flotation.

关键词： flotation frother blends bubble size coal and talc flotation

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美好时日的回忆

当代学生 2024年第6期 1-1页

作者： [奥地利]霍夫曼斯塔尔不详

这是一场睡梦,总是从一次新的苏醒进入一场新的梦境,时而占有时而失去。我看到了我遥远的童年时代,就像一池深深的山间湖水,走到里面又像进入一间房屋。这是一次拥有或什么也没有一一得到一切或什么也没有得到。它混合着儿童时代的清新... 详细信息

这是一场睡梦,总是从一次新的苏醒进入一场新的梦境,时而占有时而失去。我看到了我遥远的童年时代,就像一池深深的山间湖水,走到里面又像进入一间房屋。这是一次拥有或什么也没有一一得到一切或什么也没有得到。它混合着儿童时代的清新和死亡时期的想象,地球在蓝色的、固定不变的天际飘浮,一个死者越来越深地沉入黑暗之中,然后是向我滚来的一个果实,可是我的手太冷,太不灵活,无法将它抓到,在这种情况下我自己就像床底下的孩子一样跳出来,向它抓去。

关键词：儿童时代童年时代清新

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《眼见非实》

环球科学 2024年第9期 91-91页

作者：唐纳德·霍夫曼唐璐(译) 不详

出版:湖南科学技术出版社·原力我们总是很笃定,觉得我们眼中声色犬马的世界就是这个世界原本的样貌。但真的是这样吗?也许不是,有观点认为这些感受更像是生物在经过长时间的演化后积累起来的一些感知惯性。它是演化的结果,是一种让我... 详细信息

出版:湖南科学技术出版社·原力我们总是很笃定,觉得我们眼中声色犬马的世界就是这个世界原本的样貌。但真的是这样吗?也许不是,有观点认为这些感受更像是生物在经过长时间的演化后积累起来的一些感知惯性。它是演化的结果,是一种让我们能在纷繁复杂的外界世界中继续生存下去的简化版的指示标。无论是视觉、听觉、觉、味觉还是我们对空间的感知,都需要为生存服务。比如,你对美的感受就与繁衍紧密相关,这从基因层面就塑造了我们的感官体验。

关键词：感官体验美的感受简化版紧密相关湖南科学技术出版社感知

起泡剂对气泡大小和疏水矿物浮选性能的影响（英文）

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Journal of Central South University 2024年第07期 2280-2299页

作者： gül?ah güVEN Berivan TUN? ?.Beste AYDIN gülay BULUT Mineral Processing Engineering Department Faculty of Mines Istanbul Technical University Research Center Metso Outotec

起泡剂通过防止气泡合并来抑制气泡长大，从而产生稳定的泡沫。气泡和粒子的碰撞概率随着气泡的减少而显著增大。在相同体积系统中，大气泡分布产生的气泡较少，小气泡分布产生的气泡较多。本研究旨在将两相体系的泡沫表征参数与三相体... 详细信息

起泡剂通过防止气泡合并来抑制气泡长大，从而产生稳定的泡沫。气泡和粒子的碰撞概率随着气泡的减少而显著增大。在相同体积系统中，大气泡分布产生的气泡较少，小气泡分布产生的气泡较多。本研究旨在将两相体系的泡沫表征参数与三相体系的煤和滑石粉浮选行为相关联。为此，用甲基异丁基碳醇（MIBC）、异辛醇（2乙基己醇）、松油、Dowfroth 250泡沫剂研究单起泡剂体系和双起泡剂体系对气泡聚集的抑制作用。根据单起泡剂的结果，在最低临界聚集浓度为6×10-6时，异辛醇的气泡最小，Sauter平均直径为0.80 mm。通过混合起泡剂Dowfroth 250和松油，气泡尺寸显著减小到0.45 mm。在煤浮选中，单起泡剂和多起泡剂共混物的回收率最高，在两相体系中气泡尺寸最小，但在滑石浮选中没有发现这种关系。

关键词：浮选起泡剂混合物气泡尺寸煤和滑石浮选

Challenges and opportunities in the production of magnesium parts by directed energy deposition processes

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Journal of Magnesium and Alloys 2024年第5期12卷 1663-1686页

作者： gürel Cam Ali günen Iskenderun Technical University Faculty of Engineering and Natural SciencesDepartment of Mechanical Engineering31200 Iskenderun-HatayTurkey Iskenderun Technical University Faculty of Engineering and Natural SciencesDepartment of Metallurgy and Materials Engineering31200 Iskenderun-HatayTurkey

Mg-alloys have gained considerable attention in recent years for their outstanding properties such as lightweight,high specific strength,and corrosion resistance,making them attractive for applications in medical,aerospace,automotive,and other transport ***,their widespread application is hindered by their low formability at room temperature due to limited slip *** Mg-alloys have low mechanical properties due to the presence of casting defects such as porosity and anisotropy in addition to the high *** casting methods benefit from established process optimization techniques for these problems,additive manufacturing methods are increasingly replacing casting methods in Mg alloys as they provide more precise control over the microstructure and allow specific grain orientations,potentially enabling easier optimization of anisotropy properties in certain *** metal additive manufacturing(MAM)technology also results in some manufacturing defects such as inhomogeneous microstructural evolution and porosity and additively manufactured Mg alloy parts exhibit lower properties than the wrought parts,they in general exhibit superior properties than the cast ***,MAM is a promising technique to produce Mg alloy *** energy deposition processes,particularly wire arc directed energy deposition(WA-DED),have emerged as an advantageous additive manufacturing(AM)technique for metallic materials including magnesium alloys,offering advantages such as high deposition rates,improved material efficiency,and reduced production costs compared to subtractive ***,the inherent challenges associated with magnesium,such as its high reactivity and susceptibility to oxidation,pose unique hurdles in the application of this *** review paper delves into the progress made in the application of DED technology to Mg-alloys,its challenges,and ***,the predominant imperfections,notably inhomo

关键词： Additive manufacturing DED processes Arc-DED Wire arc additive manufacturing(WAAM) 3-D printing High deposition rate

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Recent research in mechanical properties of geopolymer-based ultrahigh-performance concrete:A review

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Defence Technology（防务技术） 2024年第2期32卷 67-88页

作者： g.Murali Division of Research&Innovation Uttaranchal UniversityDehradun 248007India

Due to the growing need for sustainable and ultra-high-strength construction materials,scientists have created an innovative ultra-high-performance concrete called geopolymer based ultra-highperformance concrete(gUHPC).Besides,in the last few decades,there have been a lot of explosions and ballistic attacks around the world,which have killed many civilians and fighters in border *** this context,this article reviews the fresh state and mechanical properties of ***,the ingredients of gUHPC and fresh properties such as setting time and flowability are briefly ***,the review of compressive strength,flexure strength,tensile strength and modulus of elasticity of fibrous ***,the blast and projectile impact resistance performance was ***,the microstructural characteristics were reviewed using the scanning electron microscope and X-ray Powder *** review outcome reveals that the mechanical properties were increased when 30%silica fume was added to a higher dose of steel fibre to improve the microstructure of *** is hypothesized that the brittleness of gUHPC was mitigated by adding 1.5%steel fibre reinforcement,which played a role in the decrease of contact explosion cratering and *** the need for cement in gUHPC was a key factor in the review,indicating a promising potential for lowering carbon ***,gUHPC research is still in its early stages,so more study is required before its full potential can be utilized.

关键词： Mechanical properties Blast Projectile impact Fibre geopolymer Silica fume Alkaline activators

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