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81.
82.
In this study, the application of response surface model in predicting and optimizing the ferro-sonication pre-treatment for degradation of bisphenol A (BPA), an endocrine disrupter compound from wastewater sludge (WWS) was investigated. The ferro-sonication pre-treatment process was carried out according to central composite design (CCD) with four independent variables such as wastewater sludge solids concentration, pH, ultrasonication time and FeSO(4) concentration. The effect of ferro-sonication pre-treatment was assessed in terms of increase in sludge solids (suspended solids (SS) and volatile solids (VS)) and organic matter (chemical oxygen demand (COD) and soluble organic carbon (SOC)) solubilization and simultaneous BPA degradation from WWS. It was observed that among all the variables studied, ultrasonication time had more significantly affected the efficiency of the ferro-sonication pre-treatment process followed by FeSO(4) and solids concentration. Through this optimization process, it was found that maximum BPA degradation of 88% could be obtained with 163 min ultrasonication time, 2.71 mg/L FeSO(4) concentration, pH 2.81 with 22 g/L SS. Further, the effect of ferro-sonication pre-treatment on biodegradation of WWS was also studied. It was observed that ultrasonication time had significant effect and the higher biodegradation (32.48%) was observed at 180 min ultrasonication time. 相似文献
83.
Sasi?Bhushan?Bhimavarapu Amit?Kumar?MaheshwariEmail author Deepti?Bhargava Shashi?Prakash?Narayan 《Journal of Materials Science》2011,46(9):3191-3199
The hot deformation behavior of Al 2024 was studied by isothermal hot compression tests in the temperature range of 250–500 °C
and strain rate range of 10−3 to 102 s−1 in a computer-controlled 50 kN servo-hydraulic universal testing machine (UTM). The results show that the flow stress of
Al 2024 alloy increases with strain rate and decreases after a peak value, indicating dynamic recovery and recrystallization.
The processing map exhibits two domains of optimum efficiency for hot deformation at different strains, including the low
strain rate domain at 500 °C and between 10−2 and 10−1 s−1 and the high strain rate domain in 250 and 300 °C in the strain rate range of 101 to 102 s−1. An attempt has been made in this article to generate a new hybrid 4D process map which illustrates contours of power dissipation
and instability in the 3D space of strain rate, temperature, and strain. 相似文献
84.
The present study deals with the shear lag phenomenon in cold formed angles under tension, which are connected on one leg. A new expression for shear lag factor which represents the net section reduction coefficient has been suggested in the present paper. The proposed expression based on the regression analysis of 108 experimental results reported in the literature is validated by experiments involving net section failure in angles under tension. Totally 18 experiments were carried out on single angles fastened with bolts to the gusset plates under tension loaded upto net section rupture mode of failure. The experimental test parameters considered are number of bolts, pitch and shear lag distances and ratio of connected leg length to unconnected leg length. The tensile capacities are evaluated by various specifications such as AS/NZS:4600:2005, NAS:2001, AISC:2005, BS:5950-Part5:1998, IS:800-2007 and the proposed equation. A comparative study of tensile capacities predicted based on various codes and the experiment results is presented in this paper. For the tested range of specimens, both NAS:2001 and AISC:2005 standards over-predicted the capacities for all the specimens. The IS:800-2007 and AS/NZS 4600:2005 predictions are good for the specimens with three bolted connections and unconservative in the case of specimen with two bolts. Both BS:5950-Part-5:1998 and the proposed equation for IS:801 predict good estimate of the tensile capacity of cold formed angle members. The proposed equation for cold formed steel tension members, which is in the same format of IS:800 (2007) (Indian code for Hot rolled steel design), has been demonstrated to be good. 相似文献
85.
The rail based urban transport system is being developed for national capital of India, New Delhi. The smoke control using
ventilation in case of fire inside the tunnel, similar to Delhi Metro corridor has been investigated using computational fluid
dynamics technique. A section of tunnel having dimensions 400 m long, 5.5 m wide and 6 m high is considered for simulation.
The analysis has been carried out by assuming a variable fire source with a peak heat release rate (HRR) of 16 MW, located
at the center of the tunnel. Ventilation ducts are located in the ceiling near the tunnel portals and are inclined at 10 degrees
to the plane of the ceiling through which fans discharge air. The influence of the fire HRR curve slope on the smoke flow
dynamics in a realistic tunnel model fitted with jet injection type longitudinal ventilation system has been investigated.
In case of fire two cases are studied: (1) fans activated immediately after detection, (2) fans activated at delayed times
to take into account the response time for the fans to achieve its maximum speed. The velocity of supply and exhaust fans
necessary to remove smoke in 30 s from the upstream direction is determined. The velocities of fan required to produce desired
critical velocity in the longitudinal direction for different HRR of fire is predicted. 相似文献
86.
Djamel Mostefa Nicolas Moreau Khalid Choukri Gerasimos Potamianos Stephen M. Chu Ambrish Tyagi Josep R. Casas Jordi Turmo Luca Cristoforetti Francesco Tobia Aristodemos Pnevmatikakis Vassilis Mylonakis Fotios Talantzis Susanne Burger Rainer Stiefelhagen Keni Bernardin Cedrick Rochet 《Language Resources and Evaluation》2007,41(3-4):389-407
87.
AS Piatek S Tyagi AC Pol A Telenti LP Miller FR Kramer D Alland 《Canadian Metallurgical Quarterly》1998,16(4):359-363
Strictureplasty for treatment of symptomatic intestinal strictures secondary to Crohn's disease is being performed with increasing frequency. To determine the overall clinical results after strictureplasty for Crohn's disease, all patients undergoing this procedure were prospectively studied. Between 6/1/89 and 2/1/97, 57 Crohn's disease patients underwent 60 operations utilizing strictureplasties. A total of 109 strictureplasties were performed (90 Heineke-Mikulicz, 6 Finney, and 13 side-to-side isoperistaltic). The 30-day perioperative morbidity was 12%, with complications being less common for patients undergoing elective versus unscheduled operations (p < 0.002). Recurrence of Crohn's disease requiring operation was seen in seven patients after a mean follow-up of 38 months. The estimated cumulative recurrence rate after 2 years was 15 +/- 6% (+/- standard error) and 22 +/- 10% at 5 years. A recurrence developed at the site of the previous strictureplasty in only five cases. Strictureplasty is a safe, effective means of providing long-term surgical palliation to selected patients with Crohn's disease. Perioperative complication rates are comparable to those seen with standard surgical treatment, and recurrences are not excessive. 相似文献
88.
A 90-nm logic technology featuring strained-silicon 总被引:10,自引:0,他引:10
Thompson S.E. Armstrong M. Auth C. Alavi M. Buehler M. Chau R. Cea S. Ghani T. Glass G. Hoffman T. Jan C.-H. Kenyon C. Klaus J. Kuhn K. Zhiyong Ma Mcintyre B. Mistry K. Murthy A. Obradovic B. Nagisetty R. Phi Nguyen Sivakumar S. Shaheed R. Shifren L. Tufts B. Tyagi S. Bohr M. El-Mansy Y. 《Electron Devices, IEEE Transactions on》2004,51(11):1790-1797
A leading-edge 90-nm technology with 1.2-nm physical gate oxide, 45-nm gate length, strained silicon, NiSi, seven layers of Cu interconnects, and low-/spl kappa/ CDO for high-performance dense logic is presented. Strained silicon is used to increase saturated n-type and p-type metal-oxide-semiconductor field-effect transistors (MOSFETs) drive currents by 10% and 25%, respectively. Using selective epitaxial Si/sub 1-x/Ge/sub x/ in the source and drain regions, longitudinal uniaxial compressive stress is introduced into the p-type MOSEFT to increase hole mobility by >50%. A tensile silicon nitride-capping layer is used to introduce tensile strain into the n-type MOSFET and enhance electron mobility by 20%. Unlike all past strained-Si work, the hole mobility enhancement in this paper is present at large vertical electric fields in nanoscale transistors making this strain technique useful for advanced logic technologies. Furthermore, using piezoresistance coefficients it is shown that significantly less strain (/spl sim/5 /spl times/) is needed for a given PMOS mobility enhancement when applied via longitudinal uniaxial compression versus in-plane biaxial tension using the conventional Si/sub 1-x/Ge/sub x/ substrate approach. 相似文献
89.
电容传感器是电容式电子清纱器的关键部件,本文着重讨论了DQS—8603型清纱器研制中电容传感器的几个问题,以促进我国清纱器的发展。 相似文献
90.
M. Kamruddin P.K. Ajikumar R. Nithya G. Mangamma A.K. Tyagi Baldev Raj 《Powder Technology》2006,161(2):145-149
Nanocrystalline ceria has been synthesized by a non-hydrolytic method using organic solvent and precipitant. The effect of the source compound on final nanocrystalline powder was investigated. The cerium nitrate hexahydrate subjected to different vacuum/thermal treatments to get cerium source compound having different extent of water of crystallization. The nanoceria, synthesized from these compounds was characterized by TGA-MS, XRD, HR-TEM and AFM. 相似文献