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51.
Yew Joon Tam Morvarid Akhavan Rezaei Mohd Lila Mohd Azmi Abdul Rani Bahaman Sewn Cen Lo 《分离科学与技术》2016,51(5):816-829
Univariate screening on factors affecting the purification performance of recombinant hepatitis B surface antigen (HBsAg) on ion exchange chromatography (IEC) and size exclusion chromatography (SEC) and the establishment of a two-step purification strategy were performed. Amongst four IEC adsorbents examined, the use of Q Sepharose XL IEC adsorbent under optimized conditions together with optimized SEC purification was able to efficiently purify HBsAg. An established purification strategy comprising the two techniques further demonstrated adaptability for scale-up operations with a final total purification factor (PF) of 94.82 ± 16.20, HBsAg purity of 95.48% and recovery yield of 78.07%. 相似文献
52.
Abdul Latif Ahmad Choe Peng Leo Syamsul Rizal Abd. Shukor 《Journal of Porous Materials》2009,16(1):33-40
Porous γ-alumina with well arranged secondary mesopores has been contrived using nanosized templating units. The pore size
of templated mesopores is precisely controlled as the pore shrinkage is insignificant. The primary pore diameter is ca. 4 nm
and the secondary pore diameter is ca. 50 nm. The porous material was characterized using N2 adsorption/desorption, TEM, XRD and FT-IR. γ-alumina with bimodal pore size distribution shows improved intra-particle diffusion
compared to γ-alumina with unimodal pore size distribution in a simple dye adsorption test. γ-alumina with different porous
structures were then impregnated with vanadium oxide for catalytic effect comparison. It was perceived that secondary pores
improve the styrene oxidation rate after the conversion of styrene reaches 30%. 相似文献
53.
54.
Lubna Sajjad Asaf Rahmatullah Jan Abdul Latif Khan Waqar Ahmad Saleem Asif Ahmed Al-Harrasi Kyung-Min Kim In-Jung Lee 《International journal of molecular sciences》2022,23(5)
The mechanism and course of Triticum plastome evolution is currently unknown; thus, it remains unclear how Triticum plastomes evolved during recent polyploidization. Here, we report the complete plastomes of two polyploid wheat species, Triticum sphaerococcum (AABBDD) and Triticum turgidum subsp. durum (AABB), and compare them with 19 available and complete Triticum plastomes to create the first map of genomic structural variation. Both T. sphaerococcum and T. turgidum subsp. durum plastomes were found to have a quadripartite structure, with plastome lengths of 134,531 bp and 134,015 bp, respectively. Furthermore, diploid (AA), tetraploid (AB, AG) and hexaploid (ABD, AGAm) Triticum species plastomes displayed a conserved gene content and commonly harbored an identical set of annotated unique genes. Overall, there was a positive correlation between the number of repeats and plastome size. In all plastomes, the number of tandem repeats was higher than the number of palindromic and forward repeats. We constructed a Triticum phylogeny based on the complete plastomes and 42 shared genes from 71 plastomes. We estimated the divergence of Hordeum vulgare from wheat around 11.04–11.9 million years ago (mya) using a well-resolved plastome tree. Similarly, Sitopsis species diverged 2.8–2.9 mya before Triticum urartu (AA) and Triticum monococcum (AA). Aegilops speltoides was shown to be the maternal donor of polyploid wheat genomes and diverged ~0.2–0.9 mya. The phylogeny and divergence time estimates presented here can act as a reference framework for future studies of Triticum evolution. 相似文献
55.
56.
Abdul Khalib Zahereel Ishwar Ehtiba Farij Omar Ahmad R. Badlishah Salim Naseer Sabri Rahman Mostafijur Li Mingfu 《Multimedia Tools and Applications》2018,77(21):28799-28816
Multimedia Tools and Applications - Adaptive Media Playout (AMP) controls adapt playout rate to prevent buffer outage and to reduce delay in playout. Most AMP techniques use buffer fullness or its... 相似文献
57.
Shojae Chaeikar Saman Zamani Mazdak Abdul Manaf Azizah Bt Zeki Akram M. 《Multimedia Tools and Applications》2018,77(1):805-835
Multimedia Tools and Applications - Steganography is the art and science of producing covert communications by concealing secret messages in apparently innocent media, while steganalysis is the art... 相似文献
58.
Khalid Tauqeer Khan Abdul Nasir Ali Mazhar Adeel Adil ur Rehman Khan Atta Shuja Junaid 《Multimedia Tools and Applications》2019,78(17):24595-24615
Multimedia Tools and Applications - The world is facing many problems including that of traffic congestion. To highlight the issue of traffic congestion worldwide specially in urban areas and to... 相似文献
59.
Efficient 3D point clouds classification for face detection using linear programming and data mining
Most of the applications related to security and biometric rely on skin region detection such as face detection, adult 3D objects filtering, and gesture recognition. In this paper, we propose a robust method for skin detection on 3D coloured point clouds. Then, we extend this method to solve the problem of 3D face detection. To do so, we construct a weighted graph from initial coloured 3D point clouds. Then, we present a linear programming algorithm using a predictive model based on a data mining approach to classify and label graph vertices as skin and non-skin regions. Moreover, we apply some refinement rules on skin regions to confirm the presence of a face. Furthermore, we demonstrate the robustness of our method by showing and analysing some experimental results. Finally, we show that our method deals with many data that can be represented by a weighted graph such as 2D images and 3D models. 相似文献
60.
An efficient numerical algorithm for multi-dimensional time dependent partial differential equations
An efficient and robust numerical scheme based on Haar wavelets and finite differences is suggested for the solution of two-dimensional time dependent linear and nonlinear partial differential equations (PDEs). Excellent feature of the scheme is the conversion of linear and non-linear PDEs to algebraic equations which are comparatively easy to handle. Convergence of the scheme, which guarantees small error norm as the resolution level increases, is also an important part of this work. Different error norms are computed to check efficiency of the technique. Computations verify accuracy, flexibility and low computational cost of the method. 相似文献