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61.
Wastewater reuse has become an attractive option for alleviating the stress from water resources. Centralized wastewater reuse is a common and continuously expanding practice worldwide, but the advantages of centralized over decentralized approaches are lately being questioned. Life cycle assessment (LCA) is a well-accepted means of assessing the overall environmental performance of service systems, however, construction of a life cycle inventory (LCI) for complex systems such as urban wastewater systems, is very time consuming. Lack of resources and unavailability of data often enforce constraints on the scope of the assessment. In such cases it may be beneficial to consider the approach presented here, which manifests the differences between the studied alternatives. By eliminating processes that remain unchanged, less data and human resources are required in building the inventory, and less parameter uncertainty is introduced into the analysis. The proposed approach is demonstrated through the conceptual modeling steps of an assessment of decentralized urban wastewater reuse alternatives.  相似文献   
62.
Synthesis, characterization and investigation of the mesogenic, thermo-morphologic and thermotropic properties of a new chiral liquid crystalline compound are presented in this work. This new compound has prolate molecules and exhibits the chiral smectic C* mesophase in a sufficiently large temperature interval. Two types of solid crystalline phases have been found in this compound. Typical textures and temperatures of the direct and reverse phase transitions, taking place in the compound, are given. Typical peculiarities for the first-order transition between the smectic C* mesophase and isotropic liquid have been observed.  相似文献   
63.
Gilboa Y  Friedler E 《Water research》2008,42(4-5):1043-1050
The microbial quality of raw greywater was found to be much better than that of municipal wastewater, with 1.6 x 10(7)cfu ml(-1) heterotrophic plate count (HPC), and 3.8 x 10(4), 9.9 x 10(3), 3.3 x 10(3) and 4.6 x 10(0)cfu 100 ml(-1) faecal coliforms (FC), Staphylococcus aureus sp., Pseudomonas aeruginosa sp. and Clostridium perfringes sp., respectively. Further, three viral indicators monitored (somatic phage, host: Escherichia coli CN(13) and F-RNA phages, hosts: E. coli F+(amp), E. coli K12) were not present in raw greywater. The greywater was treated by an RBC followed by sedimentation. The treatment removed two orders of magnitude of all bacteria. UV disinfection kinetics, survival and regrowth of HPC, FC, P. aeruginosa sp. and S. aureus sp. were examined. At doses up to 69 mW s cm(-2) FC were found to be the most resistant bacteria, followed by HPC, P. aeruginosa sp. and S. aureus sp. (inactivation rate coefficients: 0.0687, 0.113, 0.129 and 0.201 cm2 mW(-1)s(-1), respectively). At higher doses (69-439 mW s cm(-2)) all but HPC (which exhibited a tailing curve) were completely eliminated. Microscopic examination showed that FC self-aggregate in the greywater effluent. This provides FC an advantage at low doses, since the concentration of suspended matter (that can provide shelter from UV radiation) in the effluent was very low. FC, P. aeruginosa sp. and S. aureus sp. did not exhibit regrowth up to 6h after exposure to increasing UV doses (19-439 mW s cm(-2)). HPC regrowth was proven to be statistically significant in un-disinfected effluent and after irradiation with high UV doses (147 and 439 mW s cm(-2)). At these doses regrowth resulted from growth of UV-resistant bacteria due to decreased competition with other bacteria eliminated by the irradiation.  相似文献   
64.
The occurrence of mercury depletion events (MDE) in the Polar Regions during the spring periods has raised global concern due to the biomagnifications of the deposited mercury into the aquatic food chain. However, it now appears that MDE is not limited to the Polar Regions and can also occur at mid-latitudes. Diurnal cycles of mercury, ozone, and BrO behavior based on short-time resolution measurements are presented for the Dead Sea, Israel, for Summer 2006. The results show that mercury depletion events occur almost daily, accompanied always by the presence of BrO and concurrent ozone destruction. The intensity of the MDE corresponded to increasing BrO levels. Mercury depletions of more than 40% were observed when BrO levels rose above 60-70 ppt. Based on the present measurements and supported bytheoretical considerations, it appears that BrOx (BrO + Br) is the primary species responsible for the mercury depletion at the Dead Sea. The present study also suggests, especially at low ozone levels, that the Br atom may play a major role in conversion of the gaseous elemental mercury to the reactive species, HgBr2. The implications of the present study are that even at low BrO levels (<10 ppt), mercury depletion may well occur at other mid-latitude sites and thus needs to be taken into consideration in the global mercury cycle.  相似文献   
65.
66.
In their seminal work, Impagliazzo and Rudich (STOC’89) showed that no key-agreement protocol exists in the random-oracle model, yielding that key agreement cannot be black-box reduced to one-way functions. In this work, we generalize their result, showing that, to a large extent, no-private-input, semi-honest, two-party functionalities that can be securely implemented in the random oracle model can be securely implemented information theoretically (where parties are assumed to be all powerful, and no oracle is given). Using a recent information-theoretic impossibility result by McGregor et al. (FOCS’10), our result yields that certain functionalities (e.g. inner product) cannot be computed both in an accurately and in a differentially private manner in the random oracle model, implying that protocols for computing these functionalities cannot be black-box reduced to the existence of one-way functions.  相似文献   
67.

Background

We examined the effect of four weeks of ??-alanine supplementation on isometric endurance of the knee extensors at 45% maximal voluntary isometric contraction (MVIC).

Methods

Thirteen males (age 23?±?6 y; height 1.80?±?0.05?m; body mass 81.0?±?10.5?kg), matched for pre-supplementation isometric endurance, were allocated to either a placebo (n?=?6) or ??-alanine (n?=?7; 6.4?g·d-1 over 4?weeks) supplementation group. Participants completed an isometric knee extension test (IKET) to fatigue, at an intensity of 45% MVIC, before and after supplementation. In addition, two habituation tests were completed in the week prior to the pre-supplementation test and a further practice test was completed in the week prior to the post-supplementation test. MVIC force, IKET hold-time, and impulse generated were recorded.

Results

IKET hold-time increased by 9.7?±?9.4?s (13.2%) and impulse by 3.7?±?1.3 kN·s-1 (13.9%) following ??-alanine supplementation. These changes were significantly greater than those in the placebo group (IKET: t (11)?=?2.9, p ??0.05; impulse: t (11)?=?3.1, p????0.05). There were no significant changes in MVIC force in either group.

Conclusion

Four weeks of ??-alanine supplementation at 6.4?g·d-1 improved endurance capacity of the knee extensors at 45% MVIC, which most likely results from improved pH regulation within the muscle cell as a result of elevated muscle carnosine levels.  相似文献   
68.
Friedler E  Pisanty E 《Water research》2006,40(20):3751-3758
Construction costs of 55 municipal wastewater treatment plants in Israel (secondary, advanced secondary, and advanced treatment) were analysed in order to derive cost functions expressing the effects of design flow and treatment level on construction costs. Three equations were derived (statistically significant, p<0.01), one for each treatment level. These indicate that economy of scale may become weaker as treatment level rises. Analysis of the distribution of construction costs revealed negative correlation (p<0.05) between the proportional cost of civil engineering and design flow, positive correlation (p<0.05) between the proportional cost of elecromechanical equipment and design flow, and no correlation between the proportional cost of electricity and control and design flow. Operation costs were found to be 20–70% more sensitive than construction costs to treatment level. The share of operation costs as part of the total annual costs was found to increase both with design flow and treatment level, whereas the share of construction costs concurrently decreased. The implication of the findings on policy, and consequently on treatment plants performance is discussed in the last part of the paper.  相似文献   
69.
Responds to M. S. Gazzaniga's (see record 1984-07149-001) review of right-hemisphere language in split-brain patients. The present author contests Gazzaniga's assumption that, without language, right-hemisphere cognition shows no purpose, representing only an early phylogenetic and ontogenetic stage of development. The present author presents evidence from some of the same patients studied by Gazzaniga (the California series), the right hemisphere in aphasics, and language in normal right hemispheres to refute Gazzaniga's hypothesis that overall cognitive competence of the right hemisphere freezes at the time language processes are consolidated in the left hemisphere. Evidence for right-hemisphere involvement in normal language is becoming increasingly evident. (26 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
70.
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