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91.
Novel formulation for dry powder inhalation (DPI) particularly appropriate for very dilute drug concentration was developed based on the pressure swing granulation (PSG) technology. PSG was applied to the granulation of excipient lactose particles and to the coating/dusting of lactose granules with fine model drug particles. Size distribution and granule strength as well as the dispersibility of the drug particles for DPI were found to be successful for practical use. The drug particles dispersed into the respirable aerodynamic size range of 1-7 μm from the E-haler® was 53.9% for 1% coating/dusting (i.e. 1% drug in product granules) and 46.3% for 2%. E-haler® was capable of emitting 89.8% and 83.2% of drug particles charged for cases for 1% and 2% coatings, respectively.  相似文献   
92.
To prevent formation of trihalomethanes (THMs) in drinking water, removing precursors of trihalomethanes (PTHMs) in water resources for tap water is essential. We compared the following three treatments for removal of PTHMs: activated carbon (AC), ozone (OZ) and ozone-activated carbon combination (OZAC). Orange II (OR, an acidic dye), methylene blue (MB, a basic dye) and humic acid (HA) were used as PTHMs. HA exists abundantly as PTHM in nature. Results demonstrated that PTHMs could be decomposed or removed by either AC or OZ treatment. Efficiency of removal of HA by the three treatment methods was lower than that for removal of OR and MB, as the molecules of HA were larger than those of OR and MB. Decreases of total organic carbon values were achieved by treatment of MB with OZ or HA with AC. As for advanced water treatment, a two-step sequential process of OZ-AC treatments is currently used. However, the present results demonstrated that highly efficient removal of PTHMs could be accomplished by the addition of AC during OZ treatment.  相似文献   
93.
The relationship between the structure and the compressive strength of carbon fibres has been studied in detail. In order to determine the compressive strength, a combination of single-fibre composite tests and Raman spectroscopy was employed. It was found that the compressive stress–strain curves showed nonlinear behaviour, with modulus softening in compression. The compressive strengths for the fibres with a modulus ≥400 GPa were measured as ≤2 GPa and those with a modulus <400 GPa were >2 GPa. We have introduced a model to explain this behaviour that assumes that the fibres behave as composites consisting of both crystallites and amorphous carbon. It is suggested that the compressive strength is controlled by the critical stress for kinking the crystallites in the fibres. Hence, the compressive strength of carbon fibres is found to depend upon the shear modulus of the fibres and the orientation of the crystallites within them.  相似文献   
94.
Because it is the most promising method for reforming tar in a gasification system, a catalytic steam reforming reaction of tar using a dyeing sludge ash catalyst that contains mostly iron oxide has been modeled using benzene to investigate whether a steam reforming catalyst produced from waste is viable. The catalytic activity of the ash catalyst is similar to that of the commercially available iron-chrome-based catalyst for the same equivalent total amount of Fe2O3. The activity over the ash catalyst has been examined in terms of the weight hour space velocity (WHSV) and the reaction temperature to develop a model for the reaction kinetics. Using a power law model, the reaction order coefficients of the benzene and steam were estimated to be 0.43 and 0, respectively. The activation energy required for the ash catalyst was approximately 187.6 kJ mol?1. In addition, the reductive properties of the iron oxide in the ash catalyst were also examined via XRD and H2-TPR analyses.  相似文献   
95.
岩崎美术馆     
槇文彦 《建筑创作》2013,(1):276-285
日本鹿儿岛指宿/Ibusuki,Kagoshima,Japan 1978-1987指宿的强烈光线极具亚热带特色,这里的蓝天白云和冲绳的非常相似。该建筑建在近海的乡村地带,计划将其建造成为与丰田鞍池纪念馆风格迥异的别墅形式。Strong lights in Ibusuki have significant subtropical characteristics,and the blue sky and white clouds here are extremely similar to thosein Okinawa.The building is located in the offshore countryside and planned to be built into a villa whose style is g reatly different from thatof Toyota Kuragaike Commemorative Hall.正对着入口及庭院的露台(我们称之为光室)与负责主展厅顶部采光的光室相对应。在混凝土结构中,露台部分的框架尺寸堪称最小,在框架内设置有十字型的横杆。  相似文献   
96.
Rice grains develop cracks and eventually break during soaking. Since published simulation studies on hygroscopic swelling induced cracking were scarce, the present study attempts to model the mass transfer of moisture and hygroscopic swelling of rice grains using principles of finite element analysis performed in three dimensions (3D). Ultimately, to understand the crack formation in response to the existence of tensile and compressive stresses caused by moisture gradient in the grain during soaking. An empirical equation was developed to establish dependency of the diffusion coefficient of rice to both moisture content and temperature. Using a 3D replica of short grain japonica rice, the modeling was carried out using existing laws of diffusion and was validated using experimental data. Results showed that the rate of moisture diffusion and hygroscopic swelling were found to increase with increase in soaking temperature. The internal stress, however, was found to decrease with increase in soaking temperature. The simulated moisture content and increase in volume of rice grain were favorably in agreement with experimental results. Highly stressed sites that are prone to breakage have been clearly identified.  相似文献   
97.
Inoculation tests of Staphylococcus aureus were performed to evaluate the risk of toxic hazard in cheese manufacturing processes. S. aureus was inoculated into pasteurized milk or cheese curd, and the survival and growth were examined. S. aureus grew only slightly or decreased in cell number under the manufacturing condition of semi-hard type cheese or soft-type cheese. Under the conditions of the fresh cheese making process, S. aureus slightly increased in cell number, though no enterotoxin was detected. In processed cheese, S. aureus did not grow at all. Growth inhibition of S. aureus by lactic acid produced from starter culture was suggested to be the cause of growth inhibition in the natural cheese.  相似文献   
98.
The paper evaluates the adsorption of water vapor and compression strength of three types of commercially made corrugated cardboard boxes for packing strawberry, mizuna and broccoli. The experiments were conducted on the specimens and empty cardboard boxes at constant temperature and 95% relative humidity (RH). The samples were stored under the environments of two types of mists, namely nanomist and ultrasonic-mist over a period of 7 days. Nano-sized mist, which are called nanomists and defined as particles of about 60 nm in diameter, easily evaporate and are considered not to damp the corrugated boxes in comparison with the larger size ultrasonic-mists. The change in moisture content of the samples was first measured at intervals of 6, 12 and 24 h and then daily over 7 days. Compressive strength test was measured by the means of using a tensile and compression testing machine. The results revealed that moisture content of both specimen and cardboard box tests exposed to the nanomist and ultrasonic-mist at the end of experiments was 19.9% d.b. and 30.4% d.b., respectively (dry basis: g-water in material/ g-dry weight) although temperature and relative humidity were almost the same for both cases. Furthermore, the strength of cardboard specimens conditioned with nanomist after 7 days at 5.8 °C and 94.2% RH decreased by 44.3–56.9% whilst under ultrasonic-mist condition it reduced by 66.5–70% depending on the types of cardboards. Similarly, maximum compressive load of corrugated cardboard boxes exposed to nanomist and ultrasonic-mist decreased gradually over the time. It was analytically predicted that the boxes exposed to nanomist maintained its maximum compressive load at 28%, whereas those exposed to ultrasonic-mist remained at 14% after 7 days. The maximum compressive load of corrugated cardboards exponentially decreased with an increase in moisture content.  相似文献   
99.
Although most of the time drying operation aims at controlling the mean batch behavior, the quality of the final product is often related to the individual behavior of the supplied materials in a batch. The mean batch models provide limited information for quality evaluation studies. Since the initial physical and thermal properties of rice powder in a batch influence the final condition of product dried with a pneumatic dryer, a Monte Carlo simulation with initial random parameters is useful to investigate the individual behavior of rice particle during pneumatic drying. In this study, we analyzed the influence of initial moisture content and particle diameter of rice powder on the conditions of the final product in pneumatic drying process. Samples of initial moisture content and particle diameter distributions were generated by means of the covariance decomposition algorithm and Monte Carlo simulations with 5000 runs based on momentum, energy and mass balances between drying air and rice particles were performed to obtain the profiles of the response variables, rice powder temperature, moisture content and particle diameter, in a pneumatic dryer. The developed pneumatic conveying drying (PCD) model could describe the complex behavior of rice particles in a batch.  相似文献   
100.
The efficacy of vapors from polar and non-polar sub-fractions of propolis on microbial and oxidation control during rice (Oryza sativa, hinohikari var.) storage was evaluated. The sub-fractions (absolute ethanol, methylene chloride, hexane extracts: AEPEV, MCPEV and HEPEV, respectively) were infused in synthetic adsorbents and their volatiles released during storage (6 months). HEPEV, MCPEV and AEPEV treatments inhibited molding and post-inoculation bacterial colonization (1.1, 1.1, 0.9 and 1.3, 1.2, 1.1 log10 cfu/g reductions, respectively) on brown rice. AEPEV treatment suppressed fat acidity damage of milled rice at 30 °C to conventional cold storage level (5 °C) and differential Gram staining of bacteria isolated after the treatment indicated a dominant Gram-positive bacterial distribution. The concentrations providing 50% inhibition of 2′,2′-diphenylpicrylhydrazyl free radical scavenging were 9.8, 3.2 and 2.8 μg/μl for hexane (HEPE), absolute ethanol (AEPE) and methylene chloride (MCPE) extracts, respectively. The oxidative degradation rate was lowest for AEPE (4.3 × 10−4 min−1) and highest for HEPE (1.9 × 10−3 min−1) in the β-carotene bleaching assay. Gas chromatograph mass spectrometry revealed that AEPE had the highest amount of caffeic acid and caffeic acid phenethyl ester. Ultimately, the volatiles from the propolis sub-fractions had varied potential in rice quality preservation.  相似文献   
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