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排序方式: 共有1328条查询结果,搜索用时 15 毫秒
61.
Silicon - To meet the scaling targets and continue with Moore’s Law, the transition from FinFET to Gate-All-Around (GAA) nanosheet Field Effect Transistors (FETs) is the necessity for... 相似文献
62.
Flow and temperature patterns in an inductively coupled plasma reactor: Experimental measurements and CFD simulations
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Sangeeta B. Punjabi Sunil N. Sahasrabudhe S. Ghorui A. K. Das Narendra K. Joshi Dushyant C. Kothari Arijit A. Ganguli Jyeshtharaj B. Joshi 《American Institute of Chemical Engineers》2014,60(10):3647-3664
Measurements of temperature patterns in an inductively coupled plasma (ICP) have been carried out experimentally. Plasma torch was operated at different RF powers in the range of 3–14 kW at near atmospheric pressure and over a wide range of sheath gas flow rate (3–25 lpm). Measurements were made at five different axial positions in ICP torch. The chordal intensities were converted into a radial intensity profile by Abel Inversion technique. Typical radial temperature profile shows an off‐axis temperature peak, which shifts toward the wall as the power increases. Temperatures in the range of 6000–14,000 K were recorded by this method. The temperature profiles in the plasma reactor were simulated using computational fluid dynamics (CFD). A good agreement was found between the CFD predictions of the flow and temperature pattern with those published in the literature as well as the temperature profiles measured in the present work. © 2014 American Institute of Chemical Engineers AIChE J, 60: 3647–3664, 2014 相似文献
63.
Mechanical and thermal characterization of compression moulded polylactic acid natural fiber composites reinforced with hemp and lyocell fibers
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This research evaluates the effects of PLA/PP blend ratio and Lyocell/hemp mixture ratio on the morphology, water absorption, mechanical and thermal properties of PLA‐based composites. The composites were fabricated with 30 mass % hemp using compression moulding. As a reference composites made from PP were also studied. Combining of hemp and Lyocell in PLA composite leads to the reduction of moisture absorption and can improve the impact, tensile, flexural properties when compared with PLA/hemp. Composite based on the PLA/PP blend‐matrix could not improve the tensile and flexural properties compared with PLA/hemp, however; the lighter composite with better impact properties was obtained. The crystallization temperature of the PLA‐PP/hemp increased compared with pure PLA. This result was also confirmed by the SEM micrographs. The moisture absorption of PLA‐PP/hemp was higher than PLA/hemp. Based on theoretical analysis of DMTA data, there was favorable adhesion in all composites. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40534. 相似文献
64.
Lui Ng Sunny Kit-Man Wong Zheng Huang Colin Siu-Chi Lam Ariel Ka-Man Chow Dominic Chi-Chung Foo Oswens Siu-Hung Lo Roberta Wen-Chi Pang Wai-Lun Law 《International journal of molecular sciences》2022,23(3)
CD26 has been reported as a marker for colorectal cancer stem cells endowed with tumor-initiating properties and capable of colorectal cancer (CRC) metastasis. In this study, we investigated the functional effect of CD26 on CRC angiogenesis and metastasis, and the potential underlying mechanism. The functional effects of CD26 overexpression or repression were determined by a wound healing experiment, and cell migration and invasion assays in vitro and in mouse models. Differentially expressed genes regulated by CD26 were identified by genome-wide mRNA expression array and validated by quantitative PCR. CD26 functionally regulated CRC cell migration and invasion in vitro and angiogenesis and metastasis in vivo. Genome-wide mRNA expression array and qPCR showed that MMP1 was up-regulated in CD26+ subpopulation, and a subsequent experiment demonstrated the regulatory effect of CD26 on MMP1 in CRC cell lines with CD26 repression or overexpression. Furthermore, overexpression of CAV1 abrogated the CD26-regulated MMP1 induction in CRC cell lines. This study demonstrated the functional roles of CD26 in inducing CRC migration, invasion, angiogenesis and metastasis and identified the potential involvement of MMP1 and CAV1 in such process. CD26 is an attractive therapeutic target for combating tumor progression to improve the prognosis of CRC patients. 相似文献
65.
Omdeo Kishorrao Gohatre K. Jaidev Sunil S. Suresh Manoranjan Biswal Smita Mohanty Sanjay K. Nayak 《乙烯基与添加剂工艺杂志》2020,26(3):213-223
The product‐based recycling of the electrical and electronic devices and their by‐products are limited due to their complex characteristics and dissimilar material characteristics. However, such recycling procedures give clear ideas about the composition and possible recycling options of the materials present in them. Consequently, the present study deals with isolation and recycling of the major polymeric fraction present in the waste computer power supply cables (CPS) and electrical power supply (EPS) wires isolated from the household items. The composition analysis of CPS and EPS indicates that the poly(vinyl chloride) (PVC) is the major polymeric fraction along with minor content of polyethylene (PE) and polycarbonate (PC). Further, this research compares the mechanical recyclability of the PVC recovered from the CPS and EPS. Among the PVC's analyzed, PVC isolated from the EPS has been indicated superior mechanical properties. Similarly, thermal degradation analysis (TGA) indicated higher thermal stability for the PVC isolated from EPS. Besides, the flammability of the PVC specimens was studied and concluded with the possible mechanism occurring during combustion. Moreover, this study points out that PVC recovered from EPS and CPS can be mechanically recycled for the elimination of the waste. J. VINYL ADDIT. TECHNOL., 26:213–223, 2020. © 2019 Society of Plastics Engineers 相似文献
66.
Iranian Polymer Journal - This work aims at modelling and characterizing the kinetics of biodegradation of acrylic acid-grafted polypropylene. Different films of acrylic acid-grafted polypropylene... 相似文献
67.
Vishal J. Suryavanshi Makrand M. Patil Sunil B. Zanje Arjun N. Kokare Gurupad D. Kore 《分离科学与技术》2016,51(10):1690-1699
To extract iridium(III), various physicochemical parameters were studied. 2-Octylaminopyridine was used for the extraction of iridium(III) from acetate medium at 8.5 pH. Quantitative extraction of iridium(III) was achieved via ion-pair formation of cation [2-OAPH+] and anion [Ir(CH3COO)4]?. The stripping of iridium(III)-laden organic phase was carried out 2 M HCl (3 × 10 mL) . The stoichiometry of the extracted ion–pair complex was found to be 1:4:1 (metal: acetate: extractant). The extracted species [2-OAPH+. Ir(CH3COO)4?] is assumed to be an ion association product of [Ir(CH3COO)4] ? and [2-OAPH]+. The proposed method was successfully used in the separation of iridium(III) from binary and ternary mixtures. Analysis of various alloy samples was also carried out. 相似文献
68.
Sunil K. Sharma 《Fire Technology》2003,39(3):247-260
Metal-based organic complexes (MBO) are a class of FRSS additives that comprise a transition metal and an organic ligand that cleaves at an elevated temperature thereby releasing the metal in a reactive state. They help in the formation of char and thus act as an effective smoke suppressant. Use of MBO complexes as flame retardant smoke suppressants, phosphate ester as a flame retardant and active filler as endothermic material is reported here as multicomponent FRSS systems. MBOs used in the present study are the chelates of pentanediono. They were used alone as well as in combination with aluminum trihydrate (ATH) as filler were used to impart flame retardancy and smoke suppression to poly vinylchloride. Their performance was measured in terms of flammability, smoke generation, char formation and evolution of combustion gases. MBOs of molybdenum and chromium were found to be very efficient flame retardant smoke suppressants. 相似文献
69.
70.
Raj Kumar Singh Sunil Kumar Sinha A. Rama Rao 《Nuclear Engineering and Design》2009,239(10):1760-1767
The primary function of the shut down system in a nuclear reactor is to terminate any reactivity transient occurring in the core during its entire design life. Normally there is more than one system, which are independent and diverse in its mode of operation. They consist of quick acting mechanisms like dropping of safety rods by gravity, poison injection, etc. Typically in liquid poison injection system wherein high flow velocities are involved, there is significant fluid structure interaction associated with cyclic shock transients in the system. One such phenomenon has been captured and analyzed to understand the dynamics involved in the loop. The trends of loop pressure and vibration indicated presence of more than two pressure transients after complete injection of poison. The first transient arrived after 1.44 s and the second after 0.75 s. The reverse pressure pulses that manifested in the loop as a result of fast injection of fluid has been mathematically characterized by solving basic fluid balance equations. Possibility of ball lifting due to momentum pulse is also discussed. 相似文献