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The study on the solvent extraction for quantitative and selective separation of total rare earth metals from the polymetallic nodule leach liquor was investigated. The typical leach liquor bearing 0. 094 g/L total rare earth, 0. 23 g/L Mn, 0.697 g/L Cu, 0.2 g/L Fe, 0.01 g/L Co and 0.735 g/L Ni was subjected to the removal iron content by precipitation method using Ca(OH) 2 at pH 3.95, prior to solvent extraction of rare earth metals. Three different organo-phosphoric acid reagents (D2EHPA, PC88A, Cyanex 272) were used to ascertain their performances and selectivity towards the loading of rare earth metals in presence of other base metals. Based on the results of eq. pH effect, the performances of above three extractants followed the order as: D2EHPA>PC88A>Cyanex 272. To ensure the absence of extraction of base metals (Cu, Co, Ni), the eq. pH of the solution was optimized at the level of 2.21, though higher rare earth metal extraction efficiency was observed at higher eq. pH with either of the extractants. The complete process flow diagram for substantial recovery of total rare earth was developed using D2EHPA. Extraction isotherm plot was constructed at A:O=12:1, 3-stages and pH e =2.21, using 0.8 mol/L D2EHPA and the predicted condition of this study was further confirmed by 6-Cycles Counter Current Simulation (CCS) study. The stripping of total rare earth from loaded organic phase (LO) was conducted using HCl solution. Mc-Cabe Thiele diagram study carried out at A:O=1:5 using 4 mol/L HCl showed that three theoretical stages were needed for quantitative stripping of total rare earth. The subsequent stripped solution resulted thus led to contain total rare earth of 5.6 g/L indicating a very high enrichment of total metals by solvent extraction (SX) process.

The extraction of molybdenum and cobalt from spent petroleum catalyst (Co–Mo/Al 2 O 3 ) was investigated using sulphuric and nitric acid solution. Direct leaching of spent catalyst with sulphuric acid was not effective, whereas the combination of sulphuric and nitric acid was significant for the recovery of both molybdenum and cobalt. The effect of experimental factors such as reaction time, acid concentration, temperature, solid–liquid ratio and particle size were studied to determine the best conditions for the solubilisation of metal values. The parameters, temperature and nitric acid concentration are found to be critical factors especially on leaching of molybdenum from the spent catalyst. Under optimum conditions (pulp density 10% (w/v), [H 2 SO 4 ] 0.5 M, [HNO 3 ] 4.0 M, particle size 51–70 μm, temperature 50 °C and time 5 h), about 99.7% of molybdenum and 99.6% of cobalt could be extracted with 14.9% extraction of aluminium.

Baking–leaching-solvent extraction process was investigated to recover metal values from waste petroleum catalyst. Baking of Mo–Ni/Al 2 O 3 spent catalyst with H 2 SO 4 followed by leaching of the baking mass concentrate was presented. Under optimum baking condition (temp. 300 °C, H 2 SO 4 = 1.2 stoichiometric, baking time 1 h), and low acid leaching condition (temp. 95 °C, H 2 SO 4 = 2% (v/v), pulp density 5% and leaching duration 30 min), about 96% Mo, 99% Al and 95% Ni was dissolved. Baking–leaching results were interpreted by two different statistical analysis approaches namely Principal Component (PCA) and Multi Linear Regression Analysis (MLRA). The generated leach liquor was further subjected to the solvent extraction of Mo(VI) by LIX 84-I followed by aluminum using Na-Cyanex 272. A quantitative extraction of Mo(VI) and Al was achieved in 2-stage at A:O ratio of 1:1 with 40% LIX-84-I and 2-stages at 1:1 phase ratio with 60% neutralized Cyanex 272, respectively. While stripping the metals from loaded organic such as Mo(VI) using 20% NH 4 OH and Al with 3 M H 2 SO 4 , the metal concentration in the strip solution were enriched up to 1.5 times and 3 times in two and three number of stages, respectively. Based on the results of present study, a conceptual process flow diagram was proposed.

Background Following the recent elucidation of its pathogenic mechanisms involving reactive oxygen species, use of vitamins, folic acid and antioxidants as adjuvant therapy has been suggested. Objective To evaluate the long-term outcome of childhood facial vitiligo who were treated with nutritional education, vitamin E (α-tocopherol 100–400 IU/day), folic acid (1–2 mg/day) and multivitamin intake and antioxidant cosmetics as the mainstay of treatment as well as the conventional therapies including oral, topical and/or intralesional corticosteroid, topical macrolactam, Excimer laser and epidermal graft. Methods Medical data and photographs of 111 paediatric facial vitiligo patients who had been followed up for longer than 1 year from March 1, 2003 to June 30, 2013 were extracted from data warehouse of electric medical records. Photographic evaluation and final visual outcome assessment was performed. Result By investigator's assessment, 9% of patients demonstrated no improvement regardless of treatment modality, whereas 91% showed improvement of lesions. Among the latter, 33.3% resulted in >75% improvement; 18% in 50%–75% improvement; 26.1% in 25%–50% improvement; and 13.5% in

Process analytical technology (PAT) has been gaining momentum in the biotech community due to the potential for continuous real-time quality assurance resulting in improved operational control and compliance. In this two part series, we address PAT as it applies to processes that produce biotech therapeutic products. In the first part, we address evolution of the underlying concepts and applications in biopharmaceutical manufacturing. We also present a literature review of applications in the areas of upstream and downstream processing to illustrate how implementation of PAT can help realize advanced approaches to ensuring product quality in real time. In the second part, we will explore similar applications in the areas of drug product manufacturing, rapid microbiology, and chemometrics as well as evolution of PAT in biotech processing.

Implementing real-time product quality control meets one or both of the key goals outlined in FDA's PAT guidance: "variability is managed by the process" and "product quality attributes can be accurately and reliably predicted over the design space established for materials used, process parameters, manufacturing, environmental, and other conditions." The first part of the paper presented an overview of PAT concepts and applications in the areas of upstream and downstream processing. In this second part, we present principles and case studies to illustrate implementation of PAT for drug product manufacturing, rapid microbiology, and chemometrics. We further present our thoughts on how PAT will be applied to biotech processes going forward. The role of PAT as an enabling component of the Quality by Design framework is highlighted. Integration of PAT with the principles stated in the ICH Q8, Q9, and Q10 guidance documents is also discussed.

As part of the Gas Research Institute Metering Research Facility Upstream Effects programme, a sliding vane technique is used to investigate the effects of straightening vane location on orifice discharge coefficient and velocity profile in a D = 102 mm orifice meter installation. A standard ‘concentric pattern‘ 19 tube bundle straightening vane with a length to meter tube diameter ratio of 2.5 was modified so that the distance, x, from straightening vane to orifice plate could be changed rapidly without reassembling the meter tube. This paper describes sliding vane experiments made with nitrogen gas at a pressure of 724 kPa (105 psi) in 45D and 19.5D long meter tubes downstream of a single 90° elbow at a Reynolds number of 8.8 × 10 5 . Results are presented for the variation of orifice discharge coefficient for β = 0.75 as a function of sliding vane location from x/D = 5 to 42.5. Complementary results are presented for the axial velocity profile distribution measured at the orifice location in vertical and horizontal planes of the 45D meter tube by hot-film anemometer at x/D values of 5, 11, 21, 39 and 42.5.

This paper presents the degradation of f/sub T/ and f/sub max/ in CMOS devices at elevated temperature. Since MOS transistors in RF applications are usually in saturation region and f/sub T/ of CMOS devices is proportional to g/sub m/, a simple empirical model for temperature dependence of g/sub m/ at any measurement bias has been suggested by considering the temperature dependence of carrier mobility and a saturation velocity simultaneously. From the empirical temperature behavior of g/sub m/, we can predict the enhanced RF performances of CMOS at low temperature.

New experimental findings on the increase of gate and substrate current, and the enhanced device degradation of MOSFETs at elevated temperature and low gate bias have been examined. Our results show that the traditional lucky electron model does not adequately predict the temperature dependence of substrate current at low gate bias. The enhanced device degradation with temperature at low gate bias can be explained by the fact that more hot electrons are generated due to the increase of drain current and the decrease of critical energy for impact ionization.

Network management refers to monitoring and controlling network elements. There are two different prevalent communication protocols used for network management, simple network management protocol (SNMP) proposed by IAB and common management information protocol (CMIP) by ISO/OSI. In this paper, we propose an efficient approach for the integration of OSI network management and TCP/IP Internet management using SNMP. We present an architecture and techniques to menage TCP/IP Internet using OSI's common management information services (CMIS) and system management functions (SMFs). We compare services provided by SNMP with those of OSI management. The features of management information models used by SNMP and OSI management are also comparatively analyzed. Software architecture and algorithms which are necessary for the provision of management application services using SNMP are presented. >

We report progress made during the period 15 September 1991--14 September 1992 on the project ``Experimental Investigations of Electron Capture from Atomic Hydrogen and Deuterium by Alpha Particles``. In the past year we have developed reliable, narrow energy spread, high-current sources of He{sup ++} based on direct-current magentron and electron-cyclotron resonance discharges. These sources have been proven on our test bench accelerator which has been upgraded to also allow us to test atomic hydrogen effusive targets. We have thus made substantial progress toward our goal of studying single electron capture from atomic hydrogen by doubly-ionized helium. A research plan for the upcoming year is also presented.

We report progress made during the period 15 September 1991--14 September 1992 on the project Experimental Investigations of Electron Capture from Atomic Hydrogen and Deuterium by Alpha Particles''. In the past year we have developed reliable, narrow energy spread, high-current sources of He[sup ++] based on direct-current magentron and electron-cyclotron resonance discharges. These sources have been proven on our test bench accelerator which has been upgraded to also allow us to test atomic hydrogen effusive targets. We have thus made substantial progress toward our goal of studying single electron capture from atomic hydrogen by doubly-ionized helium. A research plan for the upcoming year is also presented.

An experimental description of the flow structure of non-Newtonian slurries in the laminar, transitional, and full turbulent pipe flow regimes is the primary objective of this research. Experiments were conducted in a large-scale pipe slurry flow facility with an inside pipe diameter of 51 mm. The transparent slurry formulated for these experiments from silica, mineral oil, and Stoddard solvent exhibited a yield-power-law behavior from concentric-cylinder viscometer measurements. The velocity profile for laminar flow from laser Doppler velocimeter (LDV) measurements had a central plug flow region, and it was in agreement with theory. The range of the transition region was narrower than that for a Newtonian fluid. The mean velocity profile for turbulent flow was close to a 1/7 power-law velocity profile. The rms longitudinal velocity profile was also similar to a classical turbulent pipe flow experiment for a Newtonian fluid; however, the rms tangential velocity profile was significantly different.

We have observed level specific excitation of He(n = 2, 3) in collisions of Be+ and Mg+ with He at projectile velocities of 1 2 a.u. With both Be+ and Mg+ projectiles, excitation for small scattering angles (large impact parameters) is appreciable, indicating the occurrence of “direct” excitation. Angular differential excitation cross sections were measured with Mg+ projectiles at c.m. angles up to 9.6 mrad (11.7 keV deg). “Molecular” excitation begins to dominate these cross sections at about 1.8 keV deg or b ≈ 1.5 a.u.. The total He(n = 2) excitation cross section is (6.86±0.38) × 10−18 cm2 at this velocity, as compared with a Mg+ (3s → 3p) cross section of (8.49±2.09) × 10−17 cm2.

Summary Elongation is an orderly multisite process in which, at each of about 90 growth points, two strands of murein are concurrently being synthesized, inserted and cross-linked to the sacculus. The enzymes involved move around the circumference of the cytoplasmic membrane at a rate of about 5 nm per second as new strands are being inserted, and this rate is sufficient to double the length of the cell during the cell division cycle.

Publisher Summary This chapter discusses the interactions of simple ion–atom systems. The interactions of ion–atom systems provide a unique opportunity for experimental tests of the foundations of quantum scattering theory. In the collisions of simple ion–atom systems, comparison of the experimental and theoretical results tests the quantum mechanical model of the process in situations where the fundamental interaction forces are known. The simplest three-body collision system, which consists of a proton incident on a hydrogen atom, holds the key for understanding three-body collision physics. The experimental methods employed in the study of ion–atom collisions can be divided into two classes. The classes are distinguished by the particle detected after the collision process. In one case, the primary particle is detected. In the other case, a secondary particle is detected. The secondary particle may be a photon or an electron ejected from the target or the projectile, or the nucleus of the target.

An experimental description of the flow structure of non-Newtonian slurries in the laminar, transitional, and fully-developed turbulent pipe flow regimes was the primary objective of this research. Experiments were conducted in a large-scale pipe slurry flow facility with an inside diameter of 51 mm (2 inches). Approximately, 550 liters (145 gal) of slurry were necessary in the operation of the loop. Detailed velocity profile measurements by a two-color, two-component laser Doppler anemometer (LDA) were accomplished in a transparent test section with an optically transparent slurry. These velocity measurements were apparently the first ever reported for a non-Newtonian slurry with a yield value. The transparent slurry was formulated for these experiments from silica with a particle size of one to two microns, mineral oil, and Stoddard solvent. From linear regression analysis of concentric-cylinder viscometer data, the slurry exhibited yield-power-law behavior with a yield stress of 100 dynes/cm/sup 2/, and an exponent of 0.630 for a solids concentration of 5.65% by weight. Good agreement was attained with rheological data derived from the pressure drop data in the flow loop under laminar flow conditions. The rheological properties of the transparent slurry were similar to many industrial slurries, including coal slurries, which have amore » yield value. 27 refs., 17 figs.« less

A new analytical model based on a pseudo two dimensional model is presented for the hot electron induced channel length shortening (/spl Delta/L/sub H/) of PMOSFET. It has been founded that /spl Delta/L/sub H/ is a logarithmic function of both the stress time and the degradation of punchthrough voltage, and is also a linear function of the degradation of the drain current. /spl Delta/L/sub H/ can be predicted from the measurement of the gate current (/spl Delta/L/sub H//spl prop/I/sub g//sup n/) and can thus be used for the current calculation of a degraded PMOSFET.