The effects of operational parameters such as carbon source, c/N ratio, initial nitrate concentration, temperature, and pH value on heterotrophic denitrification and functional denitrifying genes were evaluated. When ...
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The effects of operational parameters such as carbon source, c/N ratio, initial nitrate concentration, temperature, and pH value on heterotrophic denitrification and functional denitrifying genes were evaluated. When methanol was used as the sole carbon source, complete denitrification was performed in a short time without nitrous oxide (N2O) emission. complete denitrification was performed at high c/N ratios (5.14 and 12.85) and low initial nitrate concentrations (75.9 and 151.6 mg N L-1). The denitrification rate was not temperature-sensitive in the range of 25-35 degrees c, but tended to decrease at a low pH of 5-6. The relationships between N2O emission and functional genes under various operational conditions were investigated by Pearson correlation and association network analyses. The c/N ratio was a key factor for N2O emission during the heterotrophic denitrification process. This information on the denitrification performance and its association with functional gene dynamics under various operational conditions is useful for N2O mitigation strategies for wastewater treatment processes.
The paper discusses the problem of dynamic storage allocation (DSA) using c in a VMS environment. The problem is studied in a specificcontext, i.e. fault simulation of logiccircuits. However, owing to its intrinsic ...
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The paper discusses the problem of dynamic storage allocation (DSA) using c in a VMS environment. The problem is studied in a specificcontext, i.e. fault simulation of logiccircuits. However, owing to its intrinsic generality, the adopted solution can be effectively applied to a large number of similar situations. It is shown how the use of standard c-functions for dynamic memory allocation result unacceptable for efficiency reasons and different implementation strategies to solve the problem are presented.
The mixed ylide-pyridinium salts [Ph3P=c(H)c(O)cH2Nc5H5]cl (2a) and [Ph3As=c(H)c(O)cH2-Nc5H5]Br (15) have been prepared by reaction of the P and As ylides [Ph3P=c(H)c(O)cH2cl] and [Ph3As=c(H)c(O)cH2Br] (14), respectiv...
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The mixed ylide-pyridinium salts [Ph3P=c(H)c(O)cH2Nc5H5]cl (2a) and [Ph3As=c(H)c(O)cH2-Nc5H5]Br (15) have been prepared by reaction of the P and As ylides [Ph3P=c(H)c(O)cH2cl] and [Ph3As=c(H)c(O)cH2Br] (14), respectively, with pyridine. These ylides react with Pd(II) salts in the presence of bases, affording the four-membered c, c-chelated complexes cis-[Pdcl2{eta(2)-Ph3Ec(H)c(O)c( H)Nc5H5} (E = P (3), As (16)) as single diastereoisomers (meso form, RS/SR). Density functional theory (DFT) calculations revealed that the same conformational preferences are present in free mixed bis-ylides. We have established the presence of two cooperative intramolecular interactions of moderate strength by means of Bader analysis of the electron density on model free bis-ylides: the 1,4-E center dot center dot center dot O interactions (E = P, As) and the 1,6-cH center dot center dot center dot O hydrogen bonds. The intramolecular 1,4-As center dot center dot center dot O interactions have been fully characterized for the first time. These interactions play a key role in determining the preferred conformations, which then are transferred to the complexes. complex 3 reacts with AgclO4 to give the dinuclear species [Pd(mu-cl){eta(2)-Ph3Pc(H)c(O)c(H)Nc5H5}](2)(clO4)(2) (4), which further reacts with L ligands to give [Pdcl{eta(2)-Ph3Pc(H)c(O)c(H)Nc5H5}L](clO4) (L) PPh3 (6), PPhMe2 (7)) as single geometric isomers. The molecular structure of 6 has been determined by X-ray diffraction methods. complex 6 evolves in refluxing NcMe to give the ortho-metalated derivative [Pdcl(c6H4-2PPh(2)c(H)c(O)cH2Nc5H5)(PPh3)]clO4 (18). In addition, ylide 2a reacts with Ptcl2 in refluxing 2-methoxyethanol to give the ortho-platinated complex [Pt(mu-cl)(c6H4-2-PPh2c(H)c(O)cH2Nc5H5)](cl)(2) (20). The role of the electronic and steric factors in the cleavage of the halide bridging system in 4 and in the ortho-metalation reactions affording 18 and 20 is also discussed.
Dinoflagellates in the genus Symbiodinium, including nine clades(A–I), mainly form mutualistic symbioses with corals. More than 100 Symbiodinium molecular types have been identified by the ITS2-based genotype method ...
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Dinoflagellates in the genus Symbiodinium, including nine clades(A–I), mainly form mutualistic symbioses with corals. More than 100 Symbiodinium molecular types have been identified by the ITS2-based genotype method within any given clade, and specifically within Symbiodinium clade c. However, the genotype identification method using the ITS2 sequence is likely to lead to high diversity estimates due to the intra-genomic variations in the ITS2 space; thus, further validation is essential for a correct identification. In this study, the molecular diversity of Symbiodinium ITS2 sequences cloned from two stone corals, Acropora sp. SY-01 and Pocillopora sp. SY-05, and one soft coral, Sarcophyton sp. SY-07, living in the northern part of South china Sea(ScS), were analyzed and compared using the ITS2-based genotype identification method, coupled with ITS2-based secondary structural and phylogenetic analyses. As the result, 12 Symbiodinium ITS2 genotypes were identified, while only six and three Symbiodinium ITS2 genotypes were supported by ITS2-based secondary structural and phylogenetic analyses, respectively. In addition, no shared Symbiodinium ITS2 genotypes were observed among the three coral species, suggesting coral species-dependent Symbiodinium genotypes were within clade c. In summary, the present study provides a theoretical basis for validating the molecular diversity of Symbiodinium ITS2 genotypes in corals.
Extending c with arrays of variable length is critical in evolving c as a primary scientific programming language. Arrays of variable length whose size is known only at program execution time are implemented in the c-...
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Extending c with arrays of variable length is critical in evolving c as a primary scientific programming language. Arrays of variable length whose size is known only at program execution time are implemented in the c-H programming language. c-H is designed to be a superset of c. This paper describes the current implementation of arrays of variable length in the c-H programming language. It also makes comparison studies of variable length arrays in c-H with those implemented in GNU ccompiler gee and Gray Research standard ccompiler Scc as well as other alternate proposals.
As the composting industry develops rapidly in the world, the compost producers have focused on the efficiency of energy utilization in production without restricting the quality of compost in the forced ventilation s...
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As the composting industry develops rapidly in the world, the compost producers have focused on the efficiency of energy utilization in production without restricting the quality of compost in the forced ventilation systems. Therefore, this experimental study quantified the impacts of initial c/N ratio on aeration requirement and energy consumption due to aeration for reactor composting of rose pomace through kinetics of the process using fifteen 100-l composting reactors. The results of the study showed that initial c/N ratio significantly affected decomposition rate, compost maturity, and dry matter losses and organic matter losses (P < 0.05). The maximum decomposition rate (0.072 day(-1)) and the highest degree of progression of the composting process existed at the mixture with initial c/N ratio of 24.26. The results underlined the importance of the initial c/N of composting of rose pomace in terms of energy consumption due to aeration. In particular, more mature compost within a short time can be obtained when composting was operated with a c/N ratio of 23.7-25.8 in the expense of requiring more airflow rate, fan power, and energy consumption by aeration fan per composting material.
The problem of minimizing the difference of two convex functions is called polyhedral d.c. optimization problem if at least one of the two component functions is polyhedral. We characterize the existence of global opt...
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The problem of minimizing the difference of two convex functions is called polyhedral d.c. optimization problem if at least one of the two component functions is polyhedral. We characterize the existence of global optimal solutions of polyhedral d.c. optimization problems. This result is used to show that, whenever the existence of an optimal solution can be certified, polyhedral d.c. optimization problems can be solved by certain concave minimization algorithms. No further assumptions are necessary in case of the first component being polyhedral and just some mild assumptions to the first component are required for the case where the second component is polyhedral. In case of both component functions being polyhedral, we obtain a primal and dual existence test and a primal and dual solution procedure. Numerical examples are discussed.
Ultra-high temperature ceramic-modified c/ccomposites (c/c-UHTcs) were prepared by the reactive infiltration of K2MeF6 (Me = Zr, Ti) mixed with Si and Zr-Si powders. Molten salt infiltration can be divided into two s...
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Ultra-high temperature ceramic-modified c/ccomposites (c/c-UHTcs) were prepared by the reactive infiltration of K2MeF6 (Me = Zr, Ti) mixed with Si and Zr-Si powders. Molten salt infiltration can be divided into two stages: salt ion melt and Me-Si alloy melt. In the temperature range below 1400 degrees c, Zr and Si dissolve in the molten salt, are carried by the ion melt, and precipitate at the Pyc interface to form carbides. Above 1400 degrees c, a large amount of molten salt volatilises and thermally decomposes. The Me-Si alloy forms a melt and infiltrates the c/c matrix, and finally forms c/c-Zrc-Sic, c/c-Ti3Sic2-Sic, and c/c-Zrc-Tic-Siccomposites. The c/c-ZrcSiccomposite with the highest Zrccontent exhibited the lowest mass rate (2.6 +/- 0.02 mg/s) and linear ablation rate (0.82 +/- 0.04 mu m/s), which were reduced by 43.5 and 50.8 %, respectively, compared to the unmodified c/cZrc-Siccomposite.
Spherical porous hollow Fe-3(PO4)(2)/ccomposites with graftonite crystals were prepared in a mixed solvent of water and ethylene glycol by the solvothermal method. Then, olivine-structured LiFePO4/c was successfully ...
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Spherical porous hollow Fe-3(PO4)(2)/ccomposites with graftonite crystals were prepared in a mixed solvent of water and ethylene glycol by the solvothermal method. Then, olivine-structured LiFePO4/c was successfully synthesized by a solid phase reaction using Fe-3(PO4)(2)/c as the precursor mixed with nanospherical Li3PO4. The experimental results show that different proportions of mixed solvents have important effects on the morphology and carbon content of Fe-3(PO4)(2)/c, which further influence the electrochemical properties of LiFePO4/c. compared with LiFePO4/c prepared with FePO4 as the precursor, LiFePO4/c prepared using Fe-3(PO4)(2)/c with a water/ethylene glycol ratio of 1:1 as the precursor shows a better electrochemical performance with a discharge capacity of 165 mAh/g and a capacity retention rate of 96% over 100 cycles at 0.5 c. Using porous hollow Fe-3(PO4)(2)/c as the precursor for preparing LiFePO4/c is beneficial to the lithium-ion escaping and embedding during the process of charging and discharging, enhancing the discharge capacity and cycle stability of the cathode material.
Despite the effectiveness of carbon fibre reinforced polymers (cFRPs) and steel braces equipped with hysteretic dissipative devices (HYDBs) to improve the seismic performance of r.c. framed structures, the only use of...
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Despite the effectiveness of carbon fibre reinforced polymers (cFRPs) and steel braces equipped with hysteretic dissipative devices (HYDBs) to improve the seismic performance of r.c. framed structures, the only use of cFRPs may be unsatisfactory for the retrofitting of buildings designed for gravity loads only while HDYBs may be unsuitable without a preliminary upgrading. The use of cFRP and HYDB as a combined technique for the seismic retrofitting of reinforced concrete (r.c.) buildings is investigated herein. To this end, two-, four- and eight-storey r.c. framed structures are designed with reference to the structural codes for r.c. buildings in force in Italy before and after 1971. A computer code for the nonlinear static and dynamic analysis of r.c. framed structures is modified to include cFRPs and HYDBs. Firstly, the nonlinear static analysis of the original test structures is carried with the aim of improving preliminarily strength and displacement capacities by applying cFRPs laminates, at the top and bottom sides of r.c. frame members, and cFRPs wraps, at the critical end zones of columns, respectively. Then, a displacement-based design procedure of HYDBs is adopted to complete the seismic retrofitting, starting from capacity curves of the upgraded test structures. To check the reliability of the combined cFRP-HYDB technique, nonlinear dynamic analysis of the original and retrofitted structures is performed considering two sets of seven near- and far-fault ground motions scaled to the seismic design level. Results highlight that the insertion of the HYDBs is effective in reducing the seismic demand of previously upgraded cFRP structures, with Post71 types generally performing better than Ante71 ones.
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