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Hubble Scale Dark Energy Meets Nano Scale Casimir Energy and the Rational of Their T-Duality and Mirror Symmetry Equivalence
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作者 M.S.El Naschie 《World Journal of Nano Science and Engineering》 2015年第3期57-67,共11页
We establish that ordinary energy, Casimir energy and dark energy are not only interlinked but are basically the same thing separated merely by scale and topology. Casimir energy is essentially a nano scale spacetime ... We establish that ordinary energy, Casimir energy and dark energy are not only interlinked but are basically the same thing separated merely by scale and topology. Casimir energy is essentially a nano scale spacetime phenomenon produced by the boundary condition of the two Casimir plates constituting the Casimir experimental set up for measuring the Casimir force. By contrast dark energy is the result of the cosmic boundary condition, i.e. the boundary of the universe. This one sided M?bius-like boundary located at vast cosmic distance and was comparable only to the Hubble radius scales of the universe. All the Casimir energy spreads out until the majority of it reaches the vicinity of the edge of the cosmos. According to a famous theorem due to the Ukrainian-Israeli scientist I. Dvoretzky, almost 96% of the total energy will be concentrated at the boundary of the universe, too far away to be measured directly. The rest of the accumulated Casimir energy density is consequently the nearly 4% to 4.5%, the existence of which is confirmed by various sophisticated cosmic measurements and observations. When all is said and done, the work is essentially yet another confirmation of Witten’s T-duality and mirror symmetry bringing nano scale and Hubble scale together in an unexpected magical yet mathematically rigorous way. 展开更多
关键词 Mirror Symmetry Casimir Energy Dark Energy Zero Point Vacuum Energy T-DUALITY nano scale-Hubble scale Mobius Holographic Boundary Dvoretzky’s Theorem Banach-Tarski Theorem
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Effect of Surface Roughness in Micro-nano Scale on Slotted Waveguide Arrays in Ku-band
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作者 Na LI Peng LI Liwei SONG 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第3期595-603,共9页
Modeling of the roughness in micro-nano scale and its influence have not been fully investigated, however the roughness will cause amplitude and phase errors of the radiating slot, and decrease the precision and effic... Modeling of the roughness in micro-nano scale and its influence have not been fully investigated, however the roughness will cause amplitude and phase errors of the radiating slot, and decrease the precision and efficiency of the SWA in Ku-band. Firstly, the roughness is simulated using the electromechanical coupled(EC) model. The relationship between roughness and the antenna's radiation properties is obtained. For verification, an antenna proto- type is manufactured and tested, and the simulation method is introduced. According to the prototype, a contrasting experiment dealing with the flatness of the radiating plane is conducted to test the simulation method. The advantage of the EC model is validated by comparisons of the EC model and two classical roughness models (sine wave and fractal function), which shows that the EC model gives a more accurate description model for roughness, the maxi- mum error is 13%. The existence of roughness strongly broadens the beamwidth and raises the side-lobe level of SWA, which is 1.2 times greater than the ideal antenna. In addition, effect of the EC model's evaluation indices is investigated, the most affected scale of the roughness is found, which is 1/10 of the working wavelength. The proposed research provides the instruction for antenna designing and manufacturing. 展开更多
关键词 Slotted waveguide arrays - Roughness model Micro/nano-scale Amplitude and phase errors Radiationcharacteristics
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Schrodinger-Langevin Equation and Ion Transport atNano Scale
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作者 Samyadeb Bhattacharya Suman Dutta Sisir Roy 《Journal of Modern Physics》 2011年第4期231-235,共5页
Schrodinger-Langevin equation has been constructed for the ion-transport for K-ion channel. The stability of the solutions of this equation has been discussed under various physical situations. This will shed new ligh... Schrodinger-Langevin equation has been constructed for the ion-transport for K-ion channel. The stability of the solutions of this equation has been discussed under various physical situations. This will shed new light on the ion transport at nano-scale as well as the possibility of ion trapping and quantum information processing. 展开更多
关键词 Schrodinger-Langevin Equation STOCHASTIC MECHANICS LYAPUNOV Stability Ion Transport at nano scale
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Potential Applications of Nano-Scale Science and Technology in Geosciences and Experimental Studies of Nanometer-Sized Gold Adsorption on Minerals and Rocks 被引量:3
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作者 章振根 朱笑青 《Chinese Journal Of Geochemistry》 EI CAS 1997年第2期133-138,共6页
Potential applications of Nano-scale science and technology are discussed in mineralogy, ore deposits, cosmochemistry and environmental sciences. Adsorption of nanometersized gold was experimentally studied on a varie... Potential applications of Nano-scale science and technology are discussed in mineralogy, ore deposits, cosmochemistry and environmental sciences. Adsorption of nanometersized gold was experimentally studied on a variety of minerals and rocks. 展开更多
关键词 纳米技术 地球科学 地球化学 纳米金 吸收 矿物 岩石
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Experimental Study on Molecular Arrangement of Nanoscale Lubricant Films——A Review 被引量:3
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作者 ZHANG Shaohua LIU Yuhong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第5期896-903,共8页
In order to understand lubrication mechanism at the nanoscale, researchers have used many physical experimental approaches, such as surface force apparatus, atomic force microscopy and ball-on-disk tribometer. The res... In order to understand lubrication mechanism at the nanoscale, researchers have used many physical experimental approaches, such as surface force apparatus, atomic force microscopy and ball-on-disk tribometer. The results show that the variation rules of the friction force, film thicknessand viscosity of the lubricant at the nanoscale are different from elastohydrodynamic lubrication (EHL). It is speculated that these differences are attributed to the special arrangement of the molecules at the nanoscale. However, it is difficult to obtain the molecular orientation and distribution directly from the lubricant molecules in these experiments. In recent years, more and more attention has been paid to use new techniques to overcome the shortcomings of traditional experiments, including various spectral methods. The most representative achievements in the experimental research of molecular arrangement are reviewed in this paper: The change of film structure of a liquid crystal under confinement has been obtained using X-ray method. The molecular orientation change of lubricant films has been observed using absorption spectroscopy. Infrared spectroscopy has been used to measure the anisotropy of molecular orientation in the contact region when the lubricant film thickness is reduced to a few tens of nanometers. In situ Raman spectroscopy has been performed to measure the molecular orientation of the lubricant film semi-quantitatively. These results prove that confinement and shear in the contact region can change the arrangement of lubricant molecules. As a result, the lubrication characteristics are affected. The shortages of these works are also discussed based on practicable results. Further work is needed to separate the information of the solid-liquid interface from the bulk liquid film. 展开更多
关键词 nano-scale lubricating film in situ measurement molecular arrangement
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Numerical Analysis of the Adhesive Forces in Nano-Scale Structure 被引量:1
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作者 Young-Sam Cho Houkseop Han Wan-Doo Kim 《Journal of Bionic Engineering》 SCIE EI CSCD 2006年第4期209-216,共8页
Nanohairs, which can be found on the epidermis of Tokay gecko's toes, contribute to the adhesion by means of van der Waals force, capillary force, etc. This structure has inspired many researchers to fabricate the at... Nanohairs, which can be found on the epidermis of Tokay gecko's toes, contribute to the adhesion by means of van der Waals force, capillary force, etc. This structure has inspired many researchers to fabricate the attachable nano-scale structures. However, the efficiency of artificial nano-scale structures is not reliable sufficiently. Moreover, the mechanical parameters related to the nano-hair attachment are not yet revealed qualitatively. The mechanical parameters which have influence on the ability of adhesive nano-hairs were investigated through numerical simulation in which only van der Waals force was considered. For the numerical analysis, finite element method was utilized and van der Waals force, assumed as 12-6 Lennard-Jones potential, was implemented as the body force term in the finite element formulation. 展开更多
关键词 NUMERICAL analysis adhesive force nano-scale structure finite element model van der Waals force 12-6 L-J potential
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Aspects of Characterisation of Thin Coating Adhesion at the Nano-Scale
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作者 JishengE AiyangZhang 《材料导报》 EI CAS CSCD 2002年第7期5-10,共6页
In response to current development of materials in nano-science.characterisation of thin coating adhesion ona nano-scale becomes one of the most important research areas,as new coatings get ever thinner and more techn... In response to current development of materials in nano-science.characterisation of thin coating adhesion ona nano-scale becomes one of the most important research areas,as new coatings get ever thinner and more technologically advanced.With a review of technology and mechanisms of evaluating the adhesion failure of coatings.three techniques,nano-im-pact,nano-scratch and nano-indentation techniques,for charactering the adhesion of thin coatings on a nano scale are described.Results of charactering the adhesion faliure of thin coatings using three different techniques indicate that the nano scratch and nano-indentation techniques are very useful tools particularly in charactering the performance of thin coatings under nano-abra sive wear conditions.However,results from these types of tests cannot be easily applied to predict the performance of coatings whose are subject to nano-erosive wear,cyclic nano-fatigue or multiple nano-impacts during service.Instead,results of the new dynamic testing technique。 展开更多
关键词 薄膜 纳米尺度 结构 性质 特征
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Nano-scaled metal powder improving tribological properties of lubricant
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作者 万轶 熊党生 王恒志 《中国有色金属学会会刊:英文版》 CSCD 2005年第S3期167-170,共4页
Cu nanoparticles were fabricated by ball milling with the anhydrous alcohol as dispersant. The size and figure of Cu nanoparticles were characterized by X-ray diffractometry and transmission electron microscopy. The t... Cu nanoparticles were fabricated by ball milling with the anhydrous alcohol as dispersant. The size and figure of Cu nanoparticles were characterized by X-ray diffractometry and transmission electron microscopy. The tribological properties of adding Cu and MoS2 nanoparticles to the pure grease were measured on MM-200 tester, compared with the single additive and pure grease. The results show the size of Cu nanoparticles is about 50 nm. The surface with lubricant added nanopowder as additive possesses a remarkable decrease in wear volume. The friction coefficient and wear volume of lubricant mixed with 5% copper and 30% disulfide molybdenum nanoparticles are 0.09 and 1.80mm3, respectively. This mixed additive can not only increase the ability of supporting heavy load but repair the microscopic channels and cracks on the wear surface. Under higher load and long period of time, this lubricant has the characteristics of self-repairing, occluding resistance and ability of enduring higher temperature. 展开更多
关键词 nano-scaled metal powder BALL MILLING FRICTION and WEAR properties
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Nano-scale Interfacial Friction Behavior between Two Kinds of Materials in MEMS Based on Molecular Dynamics Simulations
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作者 杨平 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2006年第4期173-176,共4页
The aim of this article was to provide a systematic method to perform molecular dynamics simulotion or evaluation for nano-scale interfacial friction behavior between two kinds of materials in MEMS design. Friction is... The aim of this article was to provide a systematic method to perform molecular dynamics simulotion or evaluation for nano-scale interfacial friction behavior between two kinds of materials in MEMS design. Friction is an important factor affecting the performance and reliability of MEMS. The model of the nano-scale interracial friction behavior between two kinds of materials was presented based on the Newton' s equations of motion. The Morse potential function was selected for the model. The improved Verlet algorithm was employed to resolve the model, the atom trajectories and the law of the interfacial friction behavior. Comparisons with experimental data in other paper confirm the validity of the model. Using the model it is possible to simulate or evaluate the importance of different factors for designing of the nano-scale interfacial friction behavior between two kinds of materials in MEMS. 展开更多
关键词 molecular dynamics simulation interfacial friction nano-scale friction MEMS
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Novel Nano-scale Overlay Alignment Method for Room-temperature Imprint Lithography
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作者 WANG Li DING Yu-cheng LU Bing-heng LI Han-song YAN Le QIU Zhi-hui LIU Hong-zhong YIN Lie 《Semiconductor Photonics and Technology》 CAS 2005年第4期275-280,共6页
A novel nano-scale alignment technique based on Moiré signal for room-temperature imprint lithography in the submicron realm is proposed. The Moiré signals generated by a pair of quadruple gratings on two te... A novel nano-scale alignment technique based on Moiré signal for room-temperature imprint lithography in the submicron realm is proposed. The Moiré signals generated by a pair of quadruple gratings on two templates respectively are optically projected onto a photodetector array, then the detected Moiré signals are used to estimate the alignment errors in x and y directions. The experiment result indicates that complex differential Moiré signal is sensitive to relative displacement of the pair of marks than each single Moiré signal, and the alignment resolutions obtained in x and y directions are ±20nm(3σ) and ±24nm(3σ). They can meet the requirement of alignment accuracy for submicron imprint lithography. 展开更多
关键词 平版印刷术 光栅 纳米技术 波纹信号 空间温度
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Electronic Structure of Single-Crystal CaF<sub>2</sub>(111) with Nanoscale Phases of Ca and Si
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作者 Yokub Suvonovich Ergahov Boltakhodja Ermatovich Umirzakov Gulmira Khalmuratovna Allayarova 《Materials Sciences and Applications》 2018年第12期965-971,共7页
The impact of Ca and Si nano-scale structures on parameters and density of states of single-crystalline CaF2(111) was studied. It was shown that at low concentration of ions of Ar+ (D ≤ 5 × 1015 cm-2) one witnes... The impact of Ca and Si nano-scale structures on parameters and density of states of single-crystalline CaF2(111) was studied. It was shown that at low concentration of ions of Ar+ (D ≤ 5 × 1015 cm-2) one witnesses formation of nanoscale phases on CaF2 surface. It was revealed that these phases lead to narrowing of the forbidden band Еg between the phases by 4 - 4.5 eV. At higher concentrations (D ≈ 6 × 1016 cm-2) the surface completely is covered by Ca atoms. It was shown that deposition of θ = 10 thick Si single layer on CaF2 surface manifests island picture. The concentration of Ca and Si nano-scale phases on the surface of CaF2 and the band gap of the phases were investigated as a function of (hν) of passing light. Nano-scale phases and nano-scale films of Ca were obtained by using the technique of bombardment with ions of Ar+ of CaF2 surface. Formation of nano-scale phases were accompanied by change in the composition and structure of CaF2 zones located between the phases. These changes led to narrowing of the forbidden band of CaF2 down to 7.5 - 8 eV. The concentration of Ca and Si nano-scale phases on the surface of CaF2 and the band gap of the phases were investigated as a function of (hν) of passing light. 展开更多
关键词 nano-scale Band Gap Hetero-Structures Surface BOMBARDMENT
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Large scale silver nanowires network fabricated by MeV hydrogen (H+) ion beam irradiation
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作者 Honey S Naseem S +3 位作者 Ishaq A Maaza M Bhatti M T Wan D 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第4期268-273,共6页
A random two-dimensional large scale nano-network of silver nanowires (Ag-NWs) is fabricated by MeV hydrogen (H+) ion beam irradiation. Ag-NWs are irradiated under H+ ion beam at different ion fluences at room t... A random two-dimensional large scale nano-network of silver nanowires (Ag-NWs) is fabricated by MeV hydrogen (H+) ion beam irradiation. Ag-NWs are irradiated under H+ ion beam at different ion fluences at room temperature. The Ag-NW network is fabricated by H+ ion beam-induced welding of Ag-NWs at intersecting positions. H+ ion beam induced welding is confirmed by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Moreover, the structure of Ag NWs remains stable under H+ ion beam, and networks are optically transparent. Morphology also remains stable under H+ ion beam irradiation. No slicings or cuttings of Ag-NWs are observed under MeV H+ ion beam irradiation. The results exhibit that the formation of Ag-NW network proceeds through three steps: ion beam induced thermal spikes lead to the local heating of Ag-NWs, the formation of simple junctions on small scale, and the formation of a large scale network. This observation is useful for using Ag-NWs based devices in upper space where protons are abandoned in an energy range from MeV to GeV. This high-quality Ag-NW network can also be used as a transparent electrode for optoelectronics devices. 展开更多
关键词 Ag nanowires H+ ion irradiation nanowelding large scale nano-network optical properties
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固体力学跨尺度计算若干问题研究
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作者 庄茁 严子铭 +2 位作者 姚凯丽 崔一南 柳占立 《计算力学学报》 CAS CSCD 北大核心 2024年第1期40-46,共7页
本文展示了固体力学领域跨尺度计算的若干问题和研究概况。(1)建立位错动力学与有限元耦合DDD-FEM的计算模型,实现了能够基于纳米尺度离散位错运动机制计算分析连续介质有限变形晶体塑性问题,提出微纳尺度(200 nm~10μm)晶体塑性流动应... 本文展示了固体力学领域跨尺度计算的若干问题和研究概况。(1)建立位错动力学与有限元耦合DDD-FEM的计算模型,实现了能够基于纳米尺度离散位错运动机制计算分析连续介质有限变形晶体塑性问题,提出微纳尺度(200 nm~10μm)晶体塑性流动应力解析公式,结合试验数据揭示了在无应变梯度下强度和变形的尺寸效应;(2)建立具有微相分离结构的纳米尺度粗粒化分子动力学模型CG-MD,计算获得聚脲材料在时域和频域下的存储模量和损耗模量,通过动态加载分析的DMA试验和超声波试验的数据验证,解决了连续介质尺度下微相分离高分子共聚物的设计难题;(3)通过数据驱动关联高分辨率的微米尺度CT影像和临床低分辨率的毫米尺度CT影像的特征值,建立了围关节松质骨小梁的等效模量和结构张量,为骨组织增材制造点阵结构设计和实现个性化骨缺损重建奠定了基础。 展开更多
关键词 计算固体力学 跨尺度 微纳米晶体塑性流动应力 粗粒化分子动力学 数据驱动骨缺损重建
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Ultrastructural Findings, at Micrometric and Nanometric Scales, in Rectal and Muscular Mucosa of Patients with HIV/AIDS and Anorectal Pathology
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作者 Annunziato Maria Antonieta Sardiñ +6 位作者 as Carlos Finol Hector Carvajal Ana González Roschman De Gouveia Yetsenia García Estefanie Garibaldi Liseth 《International Journal of Clinical Medicine》 2018年第5期481-493,共13页
Objective: To determine the ultrastructural findings on Rectal Mucosa (RM) of patients with HIV/AIDS and anorectal pathologies (ARP), at micrometric and nanometric scales. Materials and methods: 5 patients were evalua... Objective: To determine the ultrastructural findings on Rectal Mucosa (RM) of patients with HIV/AIDS and anorectal pathologies (ARP), at micrometric and nanometric scales. Materials and methods: 5 patients were evaluated, 18 - 55 years old, with ARP (HIV co-infection with HPV, n = 4, and HIV-negative patient with HPV infection) (control n = 1), who were referred to the Coloproctology Unit of the HUC, and subjected to rectoscopy and biopsy. RM samples were identified, placed in a sterile plastic bottle with 1 mL of 2% glutaraldehyde and immediately transported for routine processing of fine cut (60 - 90 nm) to be evaluated via Transmission Electron Microscopy (TEM). They were fixed with Karnovsky solution with Millonig phosphate buffer (pH 7.4 and 320 mOsm) and post-fixed with OsO4 under the same conditions of pH and osmolarity. Results: Ultrastructural findings, at 10&minus;6 scale: 1) Intestinal mucosa: vacuoles of mucus of different sizes that seem to be fused. 2) Smooth muscle cells: loss of definition of contractile myofilaments mass. 3) Unmyelinated axons and terminals of Schwann cells (SC): Edema and loss of their plasma membranes in some areas of association with axon terminals as well as abundant collagen fibers associated with SC. Ultrastructural findings, at 10&minus;9 scale: 1) Smooth muscle cells: folded wrapper cores and edema of mitochondria and rough endoplasmic reticulum cisterns (RER). 2) Myelinated axon terminals: Loss of synaptic vesicles. 3) Fibroblasts: One observes mitochondria and cisterns of RER with alterations. All these alterations can generate intestinal and anorectal dysfunction in these patients. Conclusions: The HIV causes changes in rectal and muscular mucosa despite HAART treatment with undetectable viral load. 展开更多
关键词 ANORECTAL PATHOLOGIES HIV/AIDS Transmission Electron Microscopy (TEM) nanometric scales RECTAL MUCOSA CAVEOLAE Endothelial Cell nano-Drugs
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微纳尺度气液传质强化油品催化加氢反应
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作者 王立华 蔡苏杭 +3 位作者 江文涛 罗倩 罗勇 陈建峰 《化工进展》 EI CAS CSCD 北大核心 2024年第1期19-33,共15页
相比于经典的滴流床加氢技术,液相加氢技术由于其一次性投资成本和运行能耗低,受到了企业界和学术界的广泛关注。但如何进一步强化氢油相界面的传质速率来提高液相加氢效率,仍是一个重要的难题。近年来快速发展的微纳尺度气泡或液滴的... 相比于经典的滴流床加氢技术,液相加氢技术由于其一次性投资成本和运行能耗低,受到了企业界和学术界的广泛关注。但如何进一步强化氢油相界面的传质速率来提高液相加氢效率,仍是一个重要的难题。近年来快速发展的微纳尺度气泡或液滴的气液传质强化技术有助于油品催化加氢反应。本文以微纳气泡为例,首先总结了微纳气泡特点及产生方式,简述了微纳尺度气液传质强化液相加氢过程可行性判别,回顾了微纳尺度气液传质强化在油品液相加氢工艺中的相关研究及工业应用。最后分析了微纳尺度气液传质强化在油品液相加氢中面临的挑战以及发展方向,即微纳尺度传质与本征反应的匹配、工况条件微纳气泡在反应器中的流动以及含微纳气泡混合物的气液分离等。 展开更多
关键词 微纳尺度 气泡 加氢 传递过程 过程强化
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微纳富磷生物炭对土壤-苏柳系统中Cu和Pb稳定性的影响
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作者 肖江 李晓刚 +2 位作者 赵博 陈岩 陈光才 《生态环境学报》 CSCD 北大核心 2024年第3期439-449,共11页
土壤重金属污染对生态环境和人类健康造成严重威胁,生物炭作为优秀土壤改良剂,与植物联合发挥作用,是修复受重金属污染的土壤的潜力途径。以动物源生物质骨粉为原料,采用高温裂解联合湿法球磨技术,制备了两种不同粒径(<75μm和<1.... 土壤重金属污染对生态环境和人类健康造成严重威胁,生物炭作为优秀土壤改良剂,与植物联合发挥作用,是修复受重金属污染的土壤的潜力途径。以动物源生物质骨粉为原料,采用高温裂解联合湿法球磨技术,制备了两种不同粒径(<75μm和<1.0μm)的富磷生物炭(BC和MBC)。通过大棚盆栽试验,考察不同施用剂量(0、0.5%、1.0%和2.0%,w%)的BC和MBC对重金属污染土壤中Cu和Pb的赋存形态及其在苏柳172(Salix jiangsuensis ‘172’)的积累和转运影响。主要结果如下:1)通过对两种粒径的富磷生物炭进行SEM-EDS-mapping、TEM、XRD和FT-IR等分析表征,证明了富磷生物炭为含有大量的羟基磷灰石的富炭固相材料,且球磨后的MBC的比表面积和孔体积较BC可分别提升5.93倍和4.65倍;2)施用BC和MBC均能有效降低土壤Cu和Pb的生物可利用态含量,且同等剂量MBC的效果更优。在添加2%BC和MBC条件下,Cu和Pb的生物可利用态含量较对照显著降低了6.41%、17.31%和8.84%、30.31%(P<0.05);3)添加BC和MBC均显著增加了苏柳172生物量(P<0.05),显著降低了苏柳172根部中Cu和Pb的含量(P<0.05),但对苏柳172积累Cu和Pb无显著影响(P>0.05);4)BC(0-2.0%)对苏柳172的Cu和Pb生物富集和转运能力无显著影响(P>0.05),而MBC(1.0%-2%)显著提升苏柳172对Cu和Pb的生物富集和转运能力(P<0.05),2.0%MBC可使Cu和Pb的TF值分别提升101.06%和25.16%。该文对了解微纳富磷生物炭联合树木修复Cu、Pb复合污染土壤具有重要意义,可为重金属污染土壤的生态修复提供科学依据。 展开更多
关键词 生物炭 微纳米 重金属 柳树 积累 转运
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微流控技术制备多维纳米氧化锌及其应用进展
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作者 于佳 杨茜 章亚东 《现代化工》 CAS CSCD 北大核心 2024年第2期76-80,共5页
重点介绍了在微反应器中不同的反应条件对纳米ZnO形貌和粒径的影响,回顾了集成纳米ZnO的微流控器件在生物传感、催化降解和生物分离领域的具体应用,并简述了微反应器在ZnO量产方面的应用。分析表明,微流控技术为具有特定形态和功能化的... 重点介绍了在微反应器中不同的反应条件对纳米ZnO形貌和粒径的影响,回顾了集成纳米ZnO的微流控器件在生物传感、催化降解和生物分离领域的具体应用,并简述了微反应器在ZnO量产方面的应用。分析表明,微流控技术为具有特定形态和功能化的ZnO纳米材料的开发提供了新的途径;同时,三维纳米ZnO的合成丰富了纳米材料的多样性。目前的研究工作主要集中在实验室内,对于放大生产所面临的产品变质和成本高等问题还有待研究者们解决。 展开更多
关键词 微流控技术 纳米ZNO 合成 应用 放大
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碳纤维对纳米偏高岭土再生混凝土抗折强度及微观结构影响试验研究
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作者 阎杰 罗岩 +3 位作者 于旭涛 王丽君 谢军 舒新前 《复合材料科学与工程》 CAS 北大核心 2024年第1期60-65,共6页
为了充分利用再生混凝土资源,采用碳纤维对纳米偏高岭土再生混凝土抗折强度进行改性,以不同碳纤维和纳米偏高岭土掺量作为变量制备再生混凝土,结合压汞法及扫描电镜研究再生混凝土孔隙结构及微观形貌特征,分析碳纤维对纳米偏高岭土再生... 为了充分利用再生混凝土资源,采用碳纤维对纳米偏高岭土再生混凝土抗折强度进行改性,以不同碳纤维和纳米偏高岭土掺量作为变量制备再生混凝土,结合压汞法及扫描电镜研究再生混凝土孔隙结构及微观形貌特征,分析碳纤维对纳米偏高岭土再生混凝土的改性机理。结果表明:碳纤维对再生混凝土抗折强度增强效果显著,在不同纳米偏高岭土掺量下,碳纤维适配掺量有所不同,当纳米偏高岭土掺量为7%、10%、12%时,碳纤维最佳掺量分别为0.1%、0.15%、0.2%,当纳米偏高岭土掺量为10%,碳纤维掺量为0.15%时,抗折强度达到最大值,较普通再生混凝土强度增幅为59.1%;碳纤维的掺入细化了再生混凝土内部的孔隙结构,使有害孔和多害孔的比例降低,少害孔的比例增加;碳纤维在再生混凝土内部起到承载及阻裂作用,纳米偏高岭土的填充效应以及火山灰活性增强了界面过渡区的粘接强度,使碳纤维更能发挥其作用,进而促进再生混凝土强度的提高。 展开更多
关键词 碳纤维 纳米偏高岭土 再生混凝土 抗折强度 微观结构 复合材料
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仿生鲨鱼皮复合微纳减风阻结构的仿真与制备
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作者 徐征 刘日 +3 位作者 王天昊 迟振东 王作斌 李理 《实验流体力学》 CAS CSCD 北大核心 2024年第2期107-114,共8页
仿生学与减阻技术的结合,为减阻开辟了重要的研究方向,在航空航天领域有着潜在的发展与应用前景。为提高降低风阻效果,本文对复合微纳减风阻结构进行了研究,基于仿生学原理,采用CFD仿真及激光微纳制造技术,建立了减阻结构组合模型,并在... 仿生学与减阻技术的结合,为减阻开辟了重要的研究方向,在航空航天领域有着潜在的发展与应用前景。为提高降低风阻效果,本文对复合微纳减风阻结构进行了研究,基于仿生学原理,采用CFD仿真及激光微纳制造技术,建立了减阻结构组合模型,并在飞行器的大气传感器半球头体模型表面制造仿生鲨鱼皮复合微纳结构,即在仿生鲨鱼皮鳞片结构的基础上,通过激光干涉扫描二级微沟槽,以进一步提升减阻效果。采用CFD仿真与风洞实验相结合的方式,对减阻机理进行理论分析,完成了复合结构的微纳制造,减阻率最高可达10.3%。 展开更多
关键词 鲨鱼皮 减阻 风洞实验 CFD流场仿真 微纳结构 鳞片 仿生
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膜阻垢剂及其阻垢机理研究新进展 被引量:1
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作者 张子钰 何国锋 +6 位作者 王杰 李平 王义明 王勤 李莉 魏星光 郭旭虹 《华东理工大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第1期4-14,共11页
由于水资源紧缺的问题,反渗透膜处理技术发展迅速。膜阻垢剂因能减缓膜组件的结垢、提高水净化效率,因而被广泛应用于反渗透膜处理技术。常见的膜阻垢剂有磷酸盐类、阴离子聚合物类、阳离子聚合物类以及绿色阻垢剂等,一般认为它们可以... 由于水资源紧缺的问题,反渗透膜处理技术发展迅速。膜阻垢剂因能减缓膜组件的结垢、提高水净化效率,因而被广泛应用于反渗透膜处理技术。常见的膜阻垢剂有磷酸盐类、阴离子聚合物类、阳离子聚合物类以及绿色阻垢剂等,一般认为它们可以通过螯合、分散、晶格畸变等作用或阈值效应阻碍或缓解垢的形成。树枝状聚合物膜阻垢剂具有优异的阻垢性能,与其结构相似的球形聚电解质刷作为一种刷状聚合物膜阻垢剂也在膜处理领域中崭露头角。深入研究新型膜阻垢剂的阻垢机理可为设计开发针对性强、经济环保的高效阻垢产品奠定理论基础。 展开更多
关键词 反渗透膜处理技术 膜阻垢剂 膜阻垢机理 纳米球形聚电解质刷 水处理
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