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排序方式: 共有227条查询结果,搜索用时 15 毫秒
41.
Maryam Moshkelani Mariya Marinova Michel Perrier Jean Paris 《Applied Thermal Engineering》2013,50(2):1427-1436
Incorporating a biorefinery unit to an operating Kraft pulping process has significant technological, economic and social advantages over the construction of a grassroot biorefinery. Also, the conversion of a Kraft mill from total pulp making to complete biorefinery can be done in a stepwise fashion and so give a company that envisages such transformation the opportunity to master the new technologies, evaluate options and develop an appropriate business plan. In all cases however, the road to conversion presents serious challenges. As components of the wood such as lignin or hemicelluloses are withdrawn from the Kraft pulp line, the heat production capacity from the recovery boiler where they are currently burnt is diminished. At the same time the operation of the added biorefinery unit increases the steam demand. In order to avoid fossil fuel dependency, the total site must be highly integrated and optimized. The application of an intensive and innovative energy optimization methodology to actual case studies has shown that the green, low GHG emissions biorefinery is feasible. The economics can be attractive for a site combining specialty wood pulp and bio-product, biomass gasification, power cogeneration and heat upgrading by optimally positioned and designed absorption heat cycles. The methodology has been applied to biorefining technologies for lignin and hemicelluloses extraction and valorisation, both technologies being coupled with gasification of wood residue. 相似文献
42.
VD Badikov LE Zhuravleva VN Bolekhan IuG Tikhonov KV Maza?shvili 《Canadian Metallurgical Quarterly》1998,(7):17-19
The new method for microbiological analysis of blood in patients with pyoseptic infections is based on separate inoculations of plasma, erythrocyte mass, and leukocyte layer in nutrient medium providing conditions for growth of a wide spectrum of aerobes and obligate anaerobes. The method in general ensures a more rapid result and permits differentiation between true and false-positive bacteremia and between stages of septic process (bacteremia and septicemia). 相似文献
43.
44.
Andrs Gonzalez-Guerra Marta Roche-Molina Nieves García-Quintns Cristina Snchez-Ramos Daniel Martín-Prez Mariya Lytvyn Javier de Nicols-Hernndez Jos Rivera-Torres Diego F. Arroyo David Sanz-Rosa Juan A. Bernal 《International journal of molecular sciences》2021,22(16)
The continuous relationship between blood pressure (BP) and cardiovascular events makes the distinction between elevated BP and hypertension based on arbitrary cut-off values for BP. Even mild BP elevations manifesting as high-normal BP have been associated with cardiovascular risk. We hypothesize that persistent elevated BP increases atherosclerotic plaque development. To evaluate this causal link, we developed a new mouse model of elevated BP based on adeno-associated virus (AAV) gene transfer. We constructed AAV vectors to support transfer of the hRenin and hAngiotensinogen genes. A single injection of AAV-Ren/Ang (1011 total viral particles) induced sustained systolic BP increase (130 ± 20 mmHg, vs. 110 ± 15 mmHg in controls; p = 0.05). In ApoE−/− mice, AAV-induced mild BP elevation caused larger atherosclerotic lesions evaluated by histology (10-fold increase vs. normotensive controls). In this preclinical model, atheroma plaques development was attenuated by BP control with a calcium channel blocker, indicating that a small increase in BP within a physiological range has a substantial impact on plaque development in a preclinical model of atherosclerosis. These data support that non-optimal BP represents a risk for atherosclerosis development. Earlier intervention in elevated BP may prevent or delay morbidity and mortality associated with atherosclerosis. 相似文献
45.
Inherited retinal diseases (IRDs) are a heterogeneous group of disorders causing progressive loss of vision, affecting approximately one in 1000 people worldwide. Gene augmentation therapy, which typically involves using adeno-associated viral vectors for delivery of healthy gene copies to affected tissues, has shown great promise as a strategy for the treatment of IRDs. However, the use of viruses is associated with several limitations, including harmful immune responses, genome integration, and limited gene carrying capacity. Here, we review the advances in non-viral gene augmentation strategies, such as the use of plasmids with minimal bacterial backbones and scaffold/matrix attachment region (S/MAR) sequences, that have the capability to overcome these weaknesses by accommodating genes of any size and maintaining episomal transgene expression with a lower risk of eliciting an immune response. Low retinal transfection rates remain a limitation, but various strategies, including coupling the DNA with different types of chemical vehicles (nanoparticles) and the use of electrical methods such as iontophoresis and electrotransfection to aid cell entry, have shown promise in preclinical studies. Non-viral gene therapy may offer a safer and effective option for future treatment of IRDs. 相似文献
46.
Matheus Pianassola Madeline Loveday Rebecca Lalk Kimberly Pestovich Charles L. Melcher Mariya Zhuravleva 《Journal of the American Ceramic Society》2023,106(11):7123-7132
For the first time, high-entropy rare-earth monoclinic aluminate crystals were grown via directional solidification using the micro-pulling-down method. Five high-entropy compositions were formulated with a general formula RE4Al2O9, where RE is an equiatomic mixture of five rare-earth elements. The rare-earth elements included were Lu, Yb, Er, Y, Ho, Dy, Tb, Gd, Eu, Sm, Nd, and La. High-temperature powder X-ray diffraction and Rietveld structure refinement indicated that all crystals were a single monoclinic phase and that rare-earth average ionic radius did not affect phase purity. At room temperature, the refined lattice parameters increased consistently with increasing average ionic radii of the five compositions. One of the crystals had a typical high-temperature phase transition of single-RE RE4Al2O9 in the range of 1100–1150°C, which consisted of a lattice contraction upon heating. Differential scanning calorimetry indicated a thermal event corresponding to that phase transition. Electron probe microanalysis revealed Al-rich inclusions on the surface of the crystals. Crystals containing Tb had dark surface features that became lighter after annealing in a reducing atmosphere, which indicated that Tb4+ may be responsible for the dark features. 相似文献
47.
Nikolay V Tsvetkov Alexander S Gubarev Elena V Lebedeva Alexey A Lezov Mariya E Mikhailova Igor P Kolomiets Nina G Mikusheva Lilija I Akhmadeeva Nina V Kuchkina Elena S Serkova Zinaida B Shifrina 《Polymer International》2017,66(4):583-592
Hydrodynamic and optical methods were applied to study conformational and physical properties of hyperbranched pyridylphenylene polymers in dilute solutions. The samples were synthesized using Diels–Alder polycyclocondensation. It was demonstrated that hydrodynamic properties of the studied macromolecules were typical for compact non‐percolated spheres. Optical and electro‐optical methods revealed information regarding the shape and asymmetry of the macromolecules (p ≈ 1.4). The contributions of optical shape effect to the observed flow birefringence of polypyridylphenylene solutions and intrinsic anisotropy of polarizability were evaluated and analysed. It was shown that varying the polymer composition (i.e. the degree of branching) caused considerable changes in the anisotropy of optical polarizability of the polymers. Dramatic difference of the electro‐optical properties in non‐polar (toluene) and polar (tetrachloroethane) solvents was found; this difference was related to the orientational correlation of polar solvent molecules with respect to the macromolecules. Dynamic properties were studied by non‐equilibrium electric birefringence which had a reasonable agreement with the dimensions estimated from hydrodynamic data. © 2016 Society of Chemical Industry 相似文献
48.
The content of polycyclic aromatic compounds—including the strong carcinogens benz[a]pyrene and dibenz[a,h]anthracene—in coke-plant wastewater is investigated. Biochemical purification permits the removal of the following polycyclic aromatic compounds: naphthalene, acenaphthylene, fluorene, acenaphthene, phenanthrene, anthracene, fluoranthene, pyrene, and benz[k]fluoranthene (79.6–99.9% removal); and benz[a]pyrene (65.7% removal). By contrast, biochemical treatment increases the content of the following compounds in the wastewater: benz[b]fluoranthene, benz[g,h,i]perylene, and indeno[1,2,3-cd]pyrene. 相似文献
49.
We examine how the interaction between different defects influences the atom diffusivity in intermetallic systems. To solve this problem, a new model was developed which allows one to simulate the effect of the interaction of defects on their diffusivities. Based on this model, we have developed a computer program to model diffusion processes in ordered structures. For this aim we used two methods: the Monte Carlo method and the method of static relaxation. Very competitive results are obtained. These results allow us to speak with confidence about the existence of a new diffusion mechanism, which is called the dynamic pair (DP) mechanism. This mechanism is typical for the ordered structures. 相似文献
50.
Kseniya M. Achasova Elena N. Kozhevnikova Mariya A. Borisova Ekaterina A. Litvinova 《International journal of molecular sciences》2021,22(19)
The mucus layer in the intestine plays a critical role in regulation of host–microbe interactions and maintaining homeostasis. Disruptions of the mucus layer due to genetic, environmental, or immune factors may lead to inflammatory bowel diseases (IBD). IBD frequently are accompanied with infections, and therefore are treated with antibiotics. Hence, it is important to evaluate risks of antibiotic treatment in individuals with vulnerable gut barrier and chronic inflammation. Mice with a knockout of the Muc2 gene, encoding the main glycoprotein component of the mucus, demonstrate a close contact of the microbes with the gut epithelium which leads to chronic inflammation resembling IBD. Here we demonstrate that the Muc2−/− mice harboring a gut protozoan infection Tritrichomonas sp. are susceptible to an antibiotic-induced depletion of the bacterial microbiota. Suppression of the protozoan infection with efficient metronidazole dosage or L-fucose administration resulted in amelioration of an illness observed in antibiotic-treated Muc2−/− mice. Fucose is a monosaccharide presented abundantly in gut glycoproteins, including Mucin2, and is known to be involved in host–microbe interactions, in particular in microbe adhesion. We suppose that further investigation of the role of fucose in protozoan adhesion to host cells may be of great value. 相似文献