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991.
Khalid Hussain Afsheen Aman Asad Ullah Muhammad Qamar Khan Asma Ansari 《Water and Environment Journal》2024,38(1):108-120
Wastewater generated by textile industry needs to be treated to reduce its toxicity before final disposal and/or for recycling purposes. In the current study, several bacterial strains were screened for dye decolorization potential. UV–visible spectroscopy was used to determine maximum absorption wavelength of disperse dyes. HPLC and MTS assay were used to confirm the degradation and detoxification of disperse dyes, respectively. Results revealed that indigenously isolated Bacillus licheniformis, Glutamicibacter uratoxydans and Pseudomonas aeruginosa showed strong decolorization of red, blue and violet, respectively in 6–9 h. MTS assay revealed 100% viability of NIH/3T3 cell lines in presence of treated dyes. Enzyme screening assay confirmed the production of intracellular and membrane bound oxidoreductases in presence of specific dye as substrate. To resolve this issue, bacterial consortia were prepared, and better decolorization of all dyes was achieved in synergistic behaviour of Consortia 1 and 4 with 85% and 88% decolorization potential, respectively. 相似文献
992.
C S Cheow S Y Yu N K Howell Y Che Man Karidah Muhammad 《Journal of the science of food and agriculture》1999,79(6):879-885
Light microscopy studies on the fish cracker gel and expanded product (‘keropok’) emphasised the role of fish proteins in the starch expansion process. The addition of salt (20 g kg−1) in the ‘keropok’ helped to distribute evenly the starch in the fish protein. Formation of thin fish muscle bundles assisted the expansion of ‘keropok’. At 700–900 g kg−1 fish content, the fish muscle bundles formed a continuous network that caused a drop in the ‘keropok’ expansion. From the scanning electron microscopy study, ridges were found in samples (containing 600–900 g kg−1 fish content) with 20 g kg−1 salt at high magnification. © 1999 Society of Chemical Industry 相似文献
993.
Yunhai Zhao Shuo Chen Muhammad Ishaq Michel Cathelinaud Chang Yan Hongli Ma Ping Fan Xianghua Zhang Zhenghua Su Guangxing Liang 《Advanced functional materials》2024,34(8):2311992
The double gradient bandgap absorber has the potential to enhance carrier collection, improve light collection efficiency, and make the performance of solar cells more competitive. However, achieving the double gradient bandgap structure is challenging due to the comparable diffusion rates of cations during high-temperature selenization in kesterite Cu2ZnSn(S,Se)4 (CZTSSe) films. Here, it has successfully achieved a double gradient bandgap in the CZTSSe absorber by spin-coating the K2S solution during the preparation process of the precursor film. The K2S insertion serves as an additional S source for the absorber, and the high-affinity energy of K-Se causes the position of the spin-coated K2S solution locally Se-rich and S-poor. More importantly, the position of the bandgap minimum (notch) and the depth of the notch can be controlled by varying the concentration of K2S solution and its deposition stage, thereby avoiding the electronic potential barrier produced by an inadvertent notch position and depth. In addition, the K─Se liquid phase expedites the selenization process to the elimination of the fine grain layer. The champion CZTSSe device achieved an efficiency of 13.70%, indicating the potential of double gradient bandgap engineering for the future development of high-efficiency kesterite solar cells. 相似文献
994.
Weiyuan Duan Gilbert Mains Habtamu Tsegaye Gebrewold Karsten Bittkau Andreas Lambertz Binbin Xu Volker Lauterbach Alexander Eberst Nathan Nicholson Lars Korte Muhammad Ainul Yaqin Kai Zhang Qing Yang Uwe Rau Kaining Ding 《Advanced functional materials》2024,34(3):2310552
An intrinsic hydrogenated amorphous silicon (a-Si:H(i)) film and a doped silicon film are usually combined in the heterojunction contacts of silicon heterojunction (SHJ) solar cells. In this work, a post-doping process called catalytic doping (Cat-doping) on a-Si:H(i) is performed on the electron selective side of SHJ solar cells, which enables a device architecture that eliminates the additional deposition of the doped silicon layer. Thus, a single phosphorus Cat-doping layer combines the functions of two other layers by enabling excellent interface passivation and high carrier selectivity. The overall thinner layer on the window side results in higher spectral response at short wavelengths, leading to an improved short-circuit current density of 40.31 mA cm−2 and an efficiency of 23.65% (certified). The cell efficiency is currently limited by sputter damage from the subsequent transparent conductive oxide fabrication and low carrier activation in the a-Si:H(i) with Cat-doping. Numerical device simulations show that the a-Si:H(i) with Cat-doping can provide sufficient field effect passivation even at lower active carrier concentrations compared to the as-deposited doped layer, due to the lower defect density. 相似文献
995.
Aliyu Idris Muhammad Xinyu Liao Patrick J. Cullen Donghong Liu Qisen Xiang Jun Wang Shiguo Chen Xingqian Ye Tian Ding 《Comprehensive Reviews in Food Science and Food Safety》2018,17(5):1379-1394
Understanding the impact of nonthermal plasma (NTP) technology on key nutritional and functional food components is of paramount importance for the successful adoption of the technology by industry. NTP technology (NTPT) has demonstrated marked antimicrobial efficacies with good retention of important physical, chemical, sensory, and nutritional parameters for an array of food products. This paper presents the influence of NTPT on selected functional food components with a focus on low‐molecular‐weight bioactive compounds and vitamins. We discuss the mechanisms of bioactive compound alteration by plasma‐reactive species and classify their influence on vitamins and their antioxidant capacities. The impact of NTP on specific bioactive compounds depends both on plasma properties and the food matrix. Induced changes are mainly associated with oxidative degradation and cleavage of double bonds in organic compounds. The effects reported to date are mainly time‐dependent increases in the concentrations of polyphenols, vitamin C, or increases in antioxidant activity. Also, improvement in the extraction efficiency of polyphenols is observed. The review highlights future research needs regarding the complex mechanisms of interaction with plasma species. NTP is a novel technology that can both negatively and positively affect the functional components in food. 相似文献
996.
Shehu Muhammad Auwal Mohammad Zarei Chin Ping Tan 《International Journal of Food Properties》2018,21(1):1646-1660
Liposomes are used as effective nanodelivery devices to improve the physicochemical stability and biological efficacy of the encapsulated peptides and proteins. In this study, nanoliposome composite of lipoid S75-entrapped angiotensin I-converting enzyme (ACE)-inhibitory biopeptides was prepared by conventional (BLS75-CM) and direct heating (BLS75-DHM) methods. The nanoliposomes (BLS75-CM and BLS75-DHM) were stored at 4°C for 8 weeks and evaluated for physicochemical stability in terms of particle size, polydispersity index (pdi), zeta potential, and encapsulation efficiency (EE). These were also studied for residual ACE-inhibitory efficacy following their digestion under simulated gastrointestinal tract condition. The BLS75-CM was found to maintain higher physicochemical stability in terms of particle size, pdi, and zeta potential compared to BLS75-DHM. However, the BLS75-DHM indicated higher EE and efficacy with greater residual ACE-inhibitory activity of 47.37% compared to 44.18% and 36.84% that were obtained for the digested BLS75-CM and digested biopeptides without encapsulation, respectively. In vitro release study showed a cumulative biopeptides release of 66.41% and 69.00% from BLS75-CM and BLS75-DHM, respectively. The results of transmission electron microscopy showed spherical appearance of the nanoliposome capsules while Fourier Transform Infrared spectroscopy indicated the presence of ionic complexation and hydrogen bonds between the biopeptides and their phospholipid matrix. 相似文献
997.
This communique is opted to study the approximate solution of the Algebraic Lyapunov equation on the manifold of positive-definite Hermitian matrices. We choose the geodesic distance between -AHX - XA and P as the cost function, and put forward the Extended Hamiltonian algorithm (EHA) and Natural gradient algorithm (NGA) for the solution. Finally, several numerical experiments give you an idea about the effectiveness of the proposed algorithms. We also show the comparison between these two algorithms EHA and NGA. Obtained results are provided and analyzed graphically. We also conclude that the extended Hamiltonian algorithm has better convergence speed than the natural gradient algorithm, whereas the trajectory of the solution matrix is optimal in case of Natural gradient algorithm (NGA) as compared to Extended Hamiltonian Algorithm (EHA). The aim of this paper is to show that the Extended Hamiltonian algorithm (EHA) has superior convergence properties as compared to Natural gradient algorithm (NGA). Upto the best of author’s knowledge, no approximate solution of the Algebraic Lyapunov equation on the manifold of positive-definite Hermitian matrices is found so far in the literature. 相似文献
998.
In this paper, we propose a novel coverless image steganographic scheme based on a generative model. In our scheme, the secret image is first fed to the generative model database, to generate a meaning-normal and independent image different from the secret image. The generated image is then transmitted to the receiver and fed to the generative model database to generate another image visually the same as the secret image. Thus, we only need to transmit the meaning-normal image which is not related to the secret image, and we can achieve the same effect as the transmission of the secret image. This is the first time to propose the coverless image information steganographic scheme based on generative model, compared with the traditional image steganography. The transmitted image is not embedded with any information of the secret image in this method, therefore, can effectively resist steganalysis tools. Experimental results show that our scheme has high capacity, security and reliability. 相似文献
999.
Enzymolysis reaction kinetics and thermodynamics of rapeseed protein with sequential dual‐frequency ultrasound pretreatment 下载免费PDF全文
Asif Wali Haile Ma Khizar Hayat Xiaofeng Ren Zeshan Ali Yuqing Duan Muhammad Tayyab Rashid 《International Journal of Food Science & Technology》2018,53(1):72-80
We evaluated the effect of sequential dual‐frequency ultrasound (SDFU) pretreatments on rapeseed protein enzymolysis, using alcalase as a model enzyme. Hydrolysed protein concentrations, enzymolysis kinetics and thermodynamic parameters were investigated. The results showed that the hydrolysed rapeseed protein concentration following SDFU pretreatments was higher compared to that of the control for up to 75 min of enzymolysis at various substrate concentrations of 5–25 g L?1; both control and SDFU pretreatment groups showed first‐order reaction kinetics. Compared to the control, the Michaelis–Menten constant (KM) value decreased remarkably by 17.61%, while an increase in the binding frequency between enzyme and substrate (KA) by 10.47% was observed. The thermodynamic parameters, enthalpy, entropy and activation energy were reduced in the SDFU pretreatment group compared to the control by 31.78%, 18.0% and 29.56%, respectively. SDFU pretreatment showed little effect on Gibbs free energy at the various temperatures studied. 相似文献
1000.
Metallurgical and Materials Transactions B - This study provides the thermodynamic properties of the Mg-B binary alloys. Experiments were performed to measure the electromotive force (emf) as a... 相似文献