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271.
272.
Development of maximum water recovery (MWR) networks for continuous processes based on Pinch Analysis has been rather well established. In contrast, less work has been done on the water minimisation problem for batch process systems. This work presents a two-stage procedure for the synthesis of an MWR network for a batch process system, covering both mass transfer-based and non-mass transfer-based water-using processes. The first stage of the synthesis task is to locate the various network targets, which include the overall and interval-based minimum utility targets (fresh water and wastewater flows) as well as storage capacity target using the newly developed time-dependent water cascade analysis (WCA) technique. In the second stage, a new tool called the time-water network is introduced to help in the development of the MWR network to achieve the established utility targets. This new network representation has an advantage of clearly depicting the time-dependent nature of a batch water network. 相似文献
273.
Abdul Wahab Khan Mohammad Shahedur Rahman Umme Salma Zohora Masahiro Okanami Takashi Ano 《环境科学学报(英文版)》2011
Interest in microbial surfactants has been steadily increasing in recent years due to their diversity, mass production possibility, selectivity, performance under extreme conditions and potential applications in environmental protection. In this study two pentose sugars (xylose and arabinose) were investigated for the submerged fermentation (SmF) of Bacillus subtilis in surfactant production medium for bio-surfactant surfactin production. An excellent vegetative growth of B. subtilis (× 1010 CFU/mL) was observed for xylose and arabinose containing medium which were comparable to glucose supplemented medium. Low growth (× 108 CFU/mL) was found when medium was not supplemented with any of the sugars. Surfactin production in xylose, arabinose and glucose containing medium was 2700, 2600 and 2000 mg/L, respectively, whereas, medium without any sugar showed low surfactin (700 mg/L) production. These results clearly indicate the effect of pentose sugars on production of surfactin. Gradual depletion of the xylose and arabinose were confirmed by HPLC analysis during the growth phase of the strain that ultimately produced the surfactin. 相似文献
274.
Seiffert ER Nasir S Al-Harthy A Groenke JR Kraatz BP Stevens NJ Al-Sayigh AR 《Die Naturwissenschaften》2012,99(2):133-141
Despite significant recent improvements to our understanding of the early evolution of the Order Proboscidea (elephants and
their extinct relatives), geographic sampling of the group’s Paleogene fossil record remains strongly biased, with the first
~30 million years of proboscidean evolution documented solely in near-coastal deposits of northern Africa. The considerable
morphological disparity that is observable among the late Eocene and early Oligocene proboscideans of northern Africa suggests
that other, as yet unsampled, parts of Afro-Arabia might have served as important centers for the early diversification of
major proboscidean clades. Here we describe the oldest taxonomically diagnostic remains of a fossil proboscidean from the
Arabian Peninsula, a partial mandible of Omanitherium dhofarensis (new genus and species), from near the base of the early Oligocene Shizar Member of the Ashawq Formation, in the Dhofar Governorate
of the Sultanate of Oman. The molars and premolars of Omanitherium are morphologically intermediate between those of Arcanotherium and Barytherium from northern Africa, but its specialized lower incisors are unlike those of other known Paleogene proboscideans in being
greatly enlarged, high-crowned, conical, and tusk-like. Omanitherium is consistently placed close to late Eocene Barytherium in our phylogenetic analyses, and we place the new genus in the Family Barytheriidae. Some features of Omanitherium, such as tusk-like lower second incisors, the possible loss of the lower central incisors, an enlarged anterior mental foramen,
and inferred elongate mandibular symphysis and diminutive P2, suggest a possible phylogenetic link with Deinotheriidae, an extinct family of proboscideans whose origins have long been
mysterious. 相似文献
275.
Reut Loria Inon Scharf Aziz Subach Ofer Ovadia 《Behavioral ecology and sociobiology》2008,62(7):1185-1192
Antlion larvae are sand-dwelling insect predators, which ambush small arthropod prey while buried in the sand. In some species,
the larvae construct conical pits and are considered as sit-and-wait predators which seldom relocate while in other species,
they ambush prey without a pit but change their ambush site much more frequently (i.e., sit-and-pursue predators). The ability
of antlion larvae to evade some of their predators which hunt them on the sand surface is strongly constrained by the degree
of sand stabilization or by sand depth. We studied the effect of predator presence, predator type (active predatory beetle
vs. sit-and-pursue wolf spider), and sand depth (shallow vs. deep sand) on the behavioral response of the pit building Myrmeleon hyalinus larvae and the sit-and-pursue Lopezus fedtschenkoi larvae. Predator presence had a negative effect on both antlion species activity. The sit-and-wait M. hyalinus larvae showed reduced pit-building activity, whereas the sit-and-pursue L. fedtschenkoi larvae decreased relocation activity. The proportion of relocating M. hyalinus was negatively affected by sand depth, whereas L. fedtschenkoi was negatively affected also by the predator type. Specifically, the proportion of individual L. fedtschenkoi that relocated in deeper sand was lower when facing the active predator rather than the sit-and-pursue predator. The proportion
of M. hyalinus which constructed pits decreased in the presence of a predator, but this pattern was stronger when exposed to the active
predator. We suggest that these differences between the two antlion species are strongly linked to their distinct foraging
modes and to the foraging mode of their predators.
Reut Loria and Inon Scharf contributed equally to the paper. 相似文献
276.
Phytoaccumulation prospects of cadmium and zinc by mycorrhizal plant species growing in industrially polluted soils 总被引:2,自引:0,他引:2
The natural vegetation growing along a wastewater channel was subjected to analyze the uptake of Cadmium (Cd) and Zinc (Zn)
and their subsequent accumulation in aboveground and underground plant parts. Species which were mycorrhizal and growing in
soils receiving industrially contaminated wastewater were collected along with their rhizospheric soil samples. The nearby
uncontaminated control (reference) area was also subjected to sampling on similar pattern for comparison. Both Cd and Zn concentrations
were significantly higher in soils of the study area as compared to the reference site. Five plant species i.e. Desmostachya bipinnata, Dichanthium annulatum, Malvastrum coromandelianum, Saccharum bengalense, and Trifolium alexandrinum were analyzed for metal uptake. The maximum phytoaccumulation of Cd was observed in Desmostachya bipinnata (20.41 μg g−1) and Dichanthium annulatum (15.22 μg g−1) for shoot and root tissues, respectively. However, Malvastrum coromandelianum revealed maximum Zn accumulation for both the shoot and the root tissues (134 and 140 μg g−1, respectively). The examination of cleared and stained roots of the plants from both the areas studied revealed that all
of them were colonized to a lesser or a greater degree by arbuscular mycorrhizal (AM) fungi. The Cd hyperaccumulating grasses
i.e. Desmostachya bipinnata and Dichanthium annulatum, from study area had smaller root:shoot (R/S) ratio as compared to those growing on reference area indicating a negative
pressure of soil metal contamination. The lower R/S ratio in the mycorrhizal roots observed was probably due to increased
AM infection and its mediatory role in soil plant transfer of heavy metals. Furthermore, comparatively lower soil pH values
in the study areas may have played a key role in making the overall phytoavailability of both the metals. Consequently variations
in Cd and Zn tissue concentration among species were observed that also indicate the phytoaccumulation potential of the native
species. 相似文献
277.
Muhammad Nadeem Zafar Abdul Wahid Muhammad Afzal Ghauri Muhammad Zubair Muhammad Waseem Mumtaz Farooq Anwar 《毒物与环境化学》2013,95(3):422-433
This investigation describes the use of specially cultivated, nonliving biomass of Trichoderma harzianum as a biosorbent for the batch removal of Pb(II) from a stirred system under different experimental conditions. The metal removal depended upon pH, sorbent particle size, initial Pb(II) concentration, shaking speed, and sorption time. The optimal experimental conditions for the removal of Pb(II) by T. harzianum with an initial metal concentration of 100 mg L?1 were obtained at a particle size of 53 μm, a pH of 4.5, a shaking speed of 200 rpm, and a contact time of 720 min. The results were analyzed in terms of adsorption isotherms and kinetic models. The Freundlich isotherm model and pseudo second-order model fitted well in the data. T. harzianum proved to be a good biomaterial for accumulating Pb(II) from aqueous solutions (q = 460 mg g?1). 相似文献
278.
Kamaludin Roziana Othman Mohd Hafiz Dzarfan Kadir Siti Hamimah Sheikh Abdul Khan Jesmine Ismail Ahmad Fauzi Rahman Mukhlis A. Jaafar Juhana 《Environmental science and pollution research international》2023,30(1):259-273
Environmental Science and Pollution Research - Various treatments of choice are available to overcome contamination of bisphenol A (BPA) in the environment including membrane technologies; however,... 相似文献
279.
A study was carried out in Pettavaithalai area to evaluate the current status of physico-chemical contaminants and their sources in groundwater. Groundwater samples collected from pettavaithalai area in 15 different stations were analyzed every alternative months over a period of two years from August 2000 to June 2002. A sugar mill is situated at the heart of the study area. Three profiles (profile A, B and C) were selected based on the direction in which the sugar mill effluent flows. In each profile five samples were collected from five different station at a regular distance of about 1 Km. The physico-chemical parameters such as pH, EC TDS, TH, NO3, SO4, PO4, Na, K, Ca, Mg, DO, BOD and COD have been analyzed. The results showed that among the three profiles, many of the estimated physico-chemical parameters of profile C were very high when compared to profile B and A which indicates the poor quality of the groundwater around this area. 相似文献
280.
This paper examined the factors that might influence participating farmers’ willingness-to-pay for the Tree Farming Fund (TFF)
established for sustainable development of participatory forest management (PFM). Information on willingness-to-pay, socioeconomic
characteristics, and attitudes of participating farmers toward TFF were obtained from interviews with 581 participating farmers.
Logistic regression analysis was used to determine the dominant factors that might influence participating farmers’ willingness-to-pay
for the TFF. The results showed that participating farmers’ willingness-to-pay was significantly affected by (i) family income;
(ii) education level; (iii) confidence that his aspired benefits will be received; (iv) agreement with the statement that
‘PFM is sustainable under the present state of management’; (v) agreement with the statement that ‘PFM is a good strategy
for forest conservation’; and (vi) knowledge of PFM strategies. Thus, participating farmers with a higher level of education,
higher income and positive attitudes toward TFF tended to express more willingness-to-pay. Establishment of TFF could be an
effective strategy in implementing sustainable PFM in Bangladesh. For this strategy to succeed, however, active partnership
between the participating farmers and Forest Department is required. Participating farmers’ attitudes toward TFF should therefore
be taken into consideration as should the results of this study, which are important indicators of participating farmers’
positive attitudes toward TFF. 相似文献