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61.
Bisai  R.  Goel  S.  Hatwal  A.  Pal  S. K.  Majumder  A.  Nandi  T. K. 《Journal of Mining Science》2018,54(2):202-211

Improvement of energy efficiency in comminution of rocks using various pretreatment methods is being explored worldwide. This paper presents experimental data on breakage characteristics of granite and sandstone using cryogenic pre-treatment. The samples were treated with varying duration of immersion in liquid nitrogen. Combined pretreatment using oven heating followed by quenching in liquid nitrogen were also explored. The results indicate that using cryogenic pretreatment uniaxial tensile strength of granite can be decreased by more than 40% while in uniaxial compressive strength about 28% reduction is possible. For sandstone as much as 33% reduction in uniaxial compressive strength was observed.

  相似文献   
62.
High‐performance nanocomposites of NaCMC with GO are produced by solution casting. FESEM images reveal a good homogeneous dispersion of GO in the NaCMC matrix. The composite formation is facilitated by H‐bonding interaction between GO and NaCMC. Tg of the composites increases with increasing GO concentration. The storage modulus (G′) exhibits a maximum 174% increase over NaCMC at 1 wt% GO. The mechanical properties of the composites exhibit highest increase of tensile stress and Young's modulus of 188 ± 4% and 154 ± 11%, respectively, for 1 wt% GO. Analysis of Young's modulus (Ey) data using the Halpin‐Tsai equation suggests that the Ey data are close to the unidirectional orientation at >0.5 wt% GO, indicating more efficient load transfer at these compositions.

  相似文献   

63.
A new realisation scheme for third order lowpass Butterworth filter function (BFF) using two CFA devices and few RC components is presented. The design equations utilise the transadmittance elements of the devices. The maximally flat response at select frequencies in the range 5 MHz ≤ f o ≤ 30 MHz had been verified with PSPICE macromodel simulation and by hardware circuit implementation using the AD-844 device. The active sensitivities are quite low. The simulation result and the measured responses are included for f o = 5.1 MHz and 22.2 MHz.  相似文献   
64.
Recently, data hiding by modifying network parameters like packet header, payload, and packet length has become popular among researchers. Different algorithms have been proposed during the last few years which have altered the network packets in different ways to embed the data bits. Some of these algorithms modify the network packet length for embedding. Although most of the packet length based embedding schemes try to imitate the normal network traffic distribution, they have altered the statistical distribution of network packet lengths during embedding. These statistical anomalies can be exploited to detect such schemes. In this paper, a second order detection scheme for packet length based steganography has been proposed. A comprehensive set of experiments have been carried out to show that the proposed detection scheme can detect network packet length based steganography with a considerably high accuracy.  相似文献   
65.
谷氨酰胺转胺酶的功能性质及其在食品中的应用方法   总被引:15,自引:0,他引:15  
本主要论述了微生物谷氨酰胺转胺酶的性质,功能及其在食品加工工业以及开发新型食品中的应用。  相似文献   
66.
Osteomyelitis, an inflammatory process accompanied by bone destruction, is caused by infective microorganisms. The high success rates of antimicrobial therapy by conventional routes of administration in controlling most infectious diseases have not yet been achieved with osteomyelitis for several reasons. Local and sustained availability of drugs have proven to be more effective in achieving prophylactic and therapeutic outcomes. This review introduces osteomyelitis – its present options for drug delivery and their limitations, and the wide range of carrier materials and effective drug choices. Local drug delivery for osteomyelitis is a topic of importance for more than 20 years. Carrier materials used for local delivery of antibiotics may be classified as nonbiodegradable and biodegradable. Commonly used non biodegradable carrier materials are polymethyl methacrylate (PMMA), Acrylic beads, PMMA bone cement etc. and biodegradable materials are hydroxyapatite block, bioactive glass ceramics, collagen sponge, polylactide/ployglycolide implants. Both the systems release antibiotic at concentrations exceeding the minimum inhibitory concentrations (MICs) for the most common pathogens involved in osteomyelitis without causing any adverse systemic effects although non biodegradable beads are to be removed from the surgical site after completion of antibiotic release.  相似文献   
67.
International Journal of Coal Science & Technology - An open air stockpile of conical shape was formed with 3.5 m base diameter and 5 m height using 500 tons of...  相似文献   
68.
Multidimensional Systems and Signal Processing - In this paper, we consider a two-dimensional random amplitude chirp signal model. It is assumed that the additive error is independent and...  相似文献   
69.
Datta  Kashi Nath  Pramanik  Prithviraj  Bagchi  Satya  Nandi  Subrata  Saha  Sujoy 《Wireless Networks》2020,26(8):5867-5882
Wireless Networks - Neighbour discovery plays a crucial role for communication in sparsely dense mobile networks, especially in delay tolerant networks, where neighbour discovery latency is...  相似文献   
70.
Algorithms for selecting the order and estimating the parameters of an AR process, which is driven by noise having an underlying non-Gaussian distribution, from the observed noisy time series are presented. The order selection algorithm makes use of the growing memory covariance predictive least-squares (GMCPLS) criterion together with diagonal slices of the third-order cumulant plane. A triangular region of the third-order cumulant plane is used to estimate the model parameters. Extensive simulation results are presented and based on these trends, one of which has been verified using real data obtained from a rotating machine, recommendations are made on the efficacy of methods for AR order selection and parameter estimation problems  相似文献   
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