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Since the innovative work of Terada and Akiyama, asymmetric reaction using chiral Brønsted acid has attracted great attention. Asymmetric aldol reactions are extensively studied in different organocatalysis. Brønsted acid-catalyzed aldol reaction may be carried out directly without modification of the substrates or Mukaiyama type aldol reaction using silyl enol ether as nucleophiles. The reaction may proceed through the formation of enol intermediate followed by the attack to the electrophile while Mukaiyama type aldol reactions may follow two mechanistic pathways-Brønsted acidic pathways where Brønsted acid directly activates the substrate or Lewis acid pathways where Brønsted acid acts as precatalyst. Here, the recent advancement of asymmetric aldol reactions using chiral Brønsted acid as a catalyst and the fate of the catalysts in the reaction has been discussed in this review. It is observed that some kinds of aldol reactions have rarely been studied and need more attention. [ABSTRACT FROM AUTHOR]

Asiatic cotton (Gossypium arboreum) cultivated as 'desi cotton' in India, is renowned for its climate resilience and robustness against biotic and abiotic stresses. The genome of G. arboreum is therefore, considered as a valued reserve of information for discovering novel genes or gene functions for trait improvements in the present context of cotton cultivation world-wide. In the present study, we carried out genome-wide analysis of LIM gene family in desi cotton and identified twenty LIM domain proteins (GaLIMs) which include sixteen animals CRP-like GaLIMs and four plant specific GaLIMs with presence (GaDA1) or absence (GaDAR) of UIM (Ubiquitin Interacting Motifs). Among the sixteen CRP-like GaLIMs, eleven had two conventional LIM domains while, five had single LIM domain which was not reported in LIM gene family of the plant species studied, except in Brassica rapa. Phylogenetic analysis of these twenty GaLIM proteins in comparison with LIMs of Arabidopsis, chickpea and poplar categorized them into distinct αLIM1, βLIM1, γLIM2, δLIM2 groups in CRP-like LIMs, and GaDA1 and GaDAR in plant specific LIMs group. Domain analysis had revealed consensus [(C-X2-C-X17-H-X2-C)-X2-(C-X2-C-X17-C-X2-H)] and [(C-X2-C-X17-H-X2-C)-X2-(C-X4-C-X15-C-X2-H)] being conserved as first and/or second LIM domains of animal CRP-like GaLIMs, respectively. Interestingly, single LIM domain containing GaLIM15 was found to contain unique consensus with longer inter-zinc-motif spacer but shorter second zinc finger motif. All twenty GaLIMs showed variable spatio-temporal expression patterns and accordingly further categorized into distinct groups of αLIM1, βLIM1, γLIM2 δLIM2 and plant specific LIM (DA1/DAR). For the first time, response of GaDA1/DAR under the influence of biotic and abiotic stresses were studied in cotton, involving treatments with phytohormones (Jasmonic acid and Abscisic acid), salt (NaCl) and wilt causing pathogen (Fusarium oxysporum). Expressions patterns of GaDA1/DAR showed variable response and identified GaDA2 as a probable candidate gene for stress tolerance in G. arboreum. [ABSTRACT FROM AUTHOR]

Underfrequency load shedding is commonly used in the utility systems when AGC (Automatic Generation Control) cannot keep pace with the load demand and the stability of the generators can be jeopardized—undue stresses can be imposed on steam turbine blades. For an industrial system the underfrequency load shedding may have to be resorted to on loss of a source, to restore load-generation balance and prevent Undervoltages in the distribution system. It is documented that as long as the utility source is connected, there may not be any significant change in the frequency. This is because the plant generators, which are relatively small, cannot dictate the system frequency when operating in synchronism. Undervoltage load shedding can be resorted to. In both case the stability and frequency recovery characteristics of the generators must be studied. [ABSTRACT FROM AUTHOR]

Pole amplitude modulation (PAM) motor is a single-winding two speed motor used for induced draft fans. Its cost is much less than that of an adjustable speed drive motor. This paper is prompted by a rigorous study that was undertaken to replace an existing oil filled, leaky, transfer-switch type, two-speed motor starter, with an adjunct of tens of hard wired timers in a utility installation. The paper describes the fundamental operation of a PAM motor, different torque speed and thermal withstand characteristics at two speeds, and design of an alternate starter using conventional vacuum contactors with modern multifunction microprocessor relays to provide effective protection during normal two-speed operation and starting. [ABSTRACT FROM AUTHOR]

Aim: In this study, the canine endometrium tissue is characterized for its stem cell properties such as adherence to tissue culture plate (plasticity), short population doubling time, serial clonal passaging, long-term culturing properties, stem cell marker expression, and multilineage differentiation potential. Materials and Methods: The present work describes a novel isolation protocol for obtaining mesenchymal stem cells from the uterine endometrium and is compared with cells derived from umbilical cord matrix as a positive control. These cells are clonogenic, can undergo several population doublings in vitro, and can be differentiated to the osteocytes in mature mesenchymal tissues when grown in osteogenic differentiation media as detected by Alizarin Red-S staining. Results: It is reported for the first time that the cells derived from the canine endometrium (e-multipotent stem cells [MSCs]) were able to differentiate into a heterologous cell type: Osteocytes, thus demonstrating the presence of MSCs. Thus, the endometrium may be told as a potential source of MSCs which can be used for various therapeutic purposes. Conclusion: The endometrium can be used as a potential source of MSCs, which can be used for various therapeutic purposes. [ABSTRACT FROM AUTHOR]

Al doped nanocrystalline ZnO (∼30 nm) with composition Zn 1−x Al x O (0.005 < x < 0. 03) were synthesised by pyrophoric technique and sintered at 650 °C. We performed detailed electron spin resonance (ESR) studies on this system to understand the spin ordering and magnetism. The spin canting order and magneto-crystalline anisotropy obtained through ESR measurements follow each other and have a broad peak for Al doping concentration of 0.02, which also matches with the saturation magnetisation ‘M s ’ maximum, that is obtained by direct magnetisation measurement using VSM. However, it is intriguing that the spin susceptibility has a broad minimum around the same doping level (0.02). Through the ESR measurement this observed weak ferromagnetism is attributed to the spin canted magnetism in the system. Other supportive experimental data from UV–Vis, PL and Raman analysis give a clear picture of defect structures in the form of oxygen vacancies that faciliates the occurrence of room temperature ferromagnetism which of course is through spin canting mechanism. [ABSTRACT FROM AUTHOR]

A systematic investigation has been performed to study the oxidation response of Mo 76 Si 14 B 10 alloy doped with traceable amount of Ce and Al at temperature in the range of 900–1300 °C. The resistance to degradation of Mo 76 Si 14 B 10 ≥ 900 °C has increased due to the dissociation of Mo-oxides into Mo in protective glassy borosilicate layer. Addition of Ce aggrieves oxidation initially, but protection is achieved upon exposure within 3 h at all the different temperatures. No passivation has occurred in Al containing alloy due to the dissolution of Al 2 O 3 in the borosilicate scale leading to the precipitation of aluminum-borate and mullite along with unreacted cristoballite. [ABSTRACT FROM AUTHOR]

The basement in Upper Assam foreland basin exhibits a typical flexure pattern. An elongated continuous subsurface basement high has developed between Himalaya and Naga-Patkai ranges. A few prominent basement lows have developed adjacent to the foothill regions. It is noticed that the general topographic slope near the foothill regions is not only controlled by aggradation process, but also influenced by the flexured basement of the region. The basement lows have influenced the overlying topography significantly. Rivers flowing over those regions have shown unidirectional lateral migration. North bank tributaries like Subansiri, Jiadhal and Dikrang have been affected by the Subansiri basement low. Coseismic subsidence of sediments over Subansiri basement low had resulted subsidence of the North Lakhimpur-Ranga Nadi region in 1950 Assam earthquake. Some south bank tributaries like Disang and Dikhow have been affected by Nazira basement low. Topographic elevation along the Subansiri river is lower than that part of the Brahmaputra located south of Majuli. This typical topographic setting of the region makes the mouth of the Subansiri river and Majuli region highly susceptible to erosion. [ABSTRACT FROM AUTHOR]

The application of STATCOM or STATCON is common in transmission systems—the device has a capability of P-Q control in four quadrants. DSTATCOM (for distribution systems) and dynamic voltage regulator are somewhat synonymous. This paper describes a unique distribution system with three in-plant generators and an interconnection to a weak utility system at 44 kV; the three-phase short-circuit level at the utility source is only 151.7 MVA. So long as the generators are in operation, the power factor at the utility interconnection can be maintained close to unity and the voltage profiles in the system are acceptable—a total of 64 MW of load is served from 3–13.8-kV interconnected bus system. To control the voltage dips on loss of generation, 31 Mvar of capacitor filters (as the distribution system has considerable drive system loads and harmonic analysis study is conducted) are installed, yet the voltage dip can exceed 25%. A STATCOM can restore the voltage in one-half cycle. The STATCOM is also briefly compared with other technologies like TCR and TSC. [ABSTRACT FROM AUTHOR]

A heterotopic pregnancy is a rare complication of pregnancy in which both extra-uterine (ectopic pregnancy) and intrauterine pregnancy occur simultaneously. The prevalence of heterotopic pregnancy is estimated at 0.6-2.5: 10,000 pregnancy. It is a challenge for obstetrician to manage the tubal pregnancy without interruption of intrauterine pregnancy. Here we describe a case who had left tubal alive ectopic pregnancy & also intrauterine alive pregnancy simultaneously after a natural conception. This patient was managed successfully with laparoscopic left salpingectomy, and intrauterine pregnancy has been continuing. There are some precautions during laparoscopic procedure & post operative period which can help for continuation of intrauterine pregnancy. In our clinical experience, this is an extreme rare disorder and we feel interest to report this case. A heterotopic pregnancy can result from a natural conception; it requires a high index of suspicious for early and timely diagnosis; a timely intervention can result in a successful outcome of the intrauterine fetus. [ABSTRACT FROM AUTHOR]

The Lohit River is a south bank tributary of the Brahmaputra River. Till 1987, the Lohit River used to meet the Brahmaputra at a place near Bairagi Chapari (27.77°N, 95.44°E). By 1995, the confluence point had shifted about 20 km downstream. One small channel of the Lohit River captured the Dangori River during the 1988 flood. Gradually the Lohit River started flowing along the captured channel. By 1995, it became the trunk channel of the Lohit River and Dibru Saikhowa region became an island. Banklines of Brahmaputra and Lohit rivers have undergone significant changes near their confluence point within the last few decades. By 1987, the south bank of the Brahmaputra near Rohmoria (27.55°N, 95.15°E) shifted about 1.6 km southward from its position in 1973. Interestingly, within the period 1988-90 the south bank shifted about 4.1 km south. This major shifting was the result of capturing of the Dangori River by the Lohit River. However, migration of the rivers towards the south has stopped after 1995. Analysis of SRTM DEM reveals that topographic elevation has played a major role in changing the course of the Lohit River. [ABSTRACT FROM AUTHOR]

Raised intracranial pressure in the absence of an intracranial mass or hydrocephalus (BIH or pseudotumor cerebri) has been described in association with many conditions including SLE. Several pathogenic pathways tie BIH with SLE as thrombotic obliteration of cerebral arteriolar and venous systems and immune complex deposition within the arachnoid villi that are responsible for cerebrospinal fluid (CSF) absorption. The diagnosis of BIH was confirmed by increased intracranial pressure in the absence of any abnormal radiological findings of the brain. We report a young woman with SLE complicated by BIH which resolved with corticosteroid therapy and osmotic diuretics. [ABSTRACT FROM AUTHOR]

Chipper motors in pulp and paper mill environment are of special design—the stability on impact loads is one important consideration. The power factor under normal operation will continuously swing due to varying loads. This paper describes the guesswork-free rigorous calculations of pull-out (out-of-step) power factor based on the parameter of an actual installation. Single phasing is rather a rare occurrence; however, such an event has been experienced in an installation due to overheating and arcing at the fuse clips in a NEMA E2 starter of a chipper motor. Discussions on the single-phase protection of synchronous motors and recommended settings are provided. [ABSTRACT FROM AUTHOR]

This paper describes a selective high-resistance grounding (HRG) system for a large industrial facility with two in-plant generators in cogeneration mode and two utility transformers. In a five-step coordination using sensitive ground fault nondirectional and directional relays, ground faults throughout the distribution system are cleared with a maximum pickup setting of 6 A, and time delay of 0.25 s. A major consideration for HRG systems is that the stray capacitance charging current of the system should be small (10–15 A) to prevent ground fault damage. If the fault is left in place for some duration for a single-line-to-ground fault, insulation stresses occur due to higher line-to-ground voltages on two unfaulted phases. This paper demonstrates that with selective HRG, both these concerns are mitigated. A selective HRG is a bridge between the classical concepts of HRG and low-resistance grounding. The modern advancements in ground sensors and protective relaying can selectively clear low levels of ground fault currents, which make selective HRG a reality. [ABSTRACT FROM AUTHOR]

In subduction zones, sediments, hydrothermally altered lithosphere, fluids, and atmospheric gases are transported into the mantle, where ultrahigh-pressure (UHP) metamorphism takes place. However, the extent to which atmospheric noble gases are trapped in minerals crystallized during UHP metamorphism is unknown. We measured Ar and Ne trapped in phengite and omphacite from the youngest known UHP terrane on Earth to determine the composition of Ar and Ne returned from mantle depths to the surface by forearc recycling. An 40Ar/39Ar age [7.93 ± 0.10 My (1σ)] for phengite is interpreted as the timing of crystallization at mantle depths and indicates that 40Ar/39Ar phengite ages reliably record the timing of UHP metamorphism. Both phengite and omphacite yielded atmospheric 38Ar/36Ar and 20Ne/22Ne. Our study provides the first documentation, to our knowledge, of entrapment of atmospheric Ar and Ne in phengite and omphacite. Results indicate that a subduction barrier for atmospheric-derived noble gases does not exist at mantle depths associated with UHP metamorphism. We show that the crystallization age together with the isotopic composition of nonradiogenic noble gases trapped in minerals formed during subsolidus crystallization at mantle depths can be used to unambiguously assess forearc recycling of atmospheric noble gases. The flux of atmospheric noble gas entering the deep Earth through subduction and returning to the surface cannot be fully realized until the abundances of atmospheric noble gases trapped in exhumed UHP rocks are known. [ABSTRACT FROM AUTHOR]

Micrometer-sized γ−Ni dendrite reinforced nanoeutectic matrix composites have been developed in (Ni 0.92 Zr 0.08 ) 100– x Al x (0 ≤ x ≤ 4) by arc melting. The eutectic matrix is composed of alternate nano-lamellae of intermetallic Ni 5 Zr and fcc–Ni solid solution phases. All these composites exhibit very high strength, large compressive plasticity ∼25% and strain-hardening up to 1780 MPa. Al dissolves in γ−Ni(Zr) solid solution phase, decreases its hardness/strength, and increases the volume % of γ−Ni dendrite from 20% ( x = 0) to 29% ( x = 4). Whereas, refinement of the eutectic lamellae thickness from 275 nm ( x = 0) to 160 nm ( x = 4) increases the matrix hardness and retains the global strength of the composites. The effect of Al addition on the microstructure formation, volume fraction as well as the length scale of the constituent phases, and mechanical properties, have been discussed using an analytical model. [ABSTRACT FROM AUTHOR]

Polycrystalline Zn1-x(Mn:Ni)x0 sample for x = 0.02 were synthesized by solid state route. We have observed low field microwave absorption in these powder samples. Low field microwave absorption signal is out of phase with the regular resonance signal indicating the microwave absorption has a minimum at zero field and the absorption of microwaves increases with increase of magnetic field. Low field microwave absorption in these powders is qualitatively different from their bulk pellets. Temperature dependence of the low field microwave absorption indicates a line shape evolution and a non-monotonic peak to peak intensity change. Further, we have observed the absence of 2nd harmonic in this low field microwave absorption, indicating low field microwave absorption in these transition metal co-doped ZnO powders is not non-linear in nature. [ABSTRACT FROM AUTHOR]

The design and application of second-order high-pass filters are described for 2-8000-hp ID fan drives, which reduces the voltage harmonic distortion at point of common coupling (PCC) from a high value of 42.41% to 1.32% and also brings the current distortion at PCC within IEEE 519 limits. Failure of the electronic components of the 8000-hp ID fan drives and shutdown of electronic loads downstream of the main 13.8-kV buses were observed, which led to investigation of harmonic problems and their mitigation. The second-order high-pass filters are applied for the first time in industry for such a harmonic distortion problem. [ABSTRACT FROM PUBLISHER]

Ascaris infestation that too causing biliary obstruction is very rare in infancy even in endemic area. Adult Ascaris diameter (3-6 mm) is more than the average diameter of CBD in paediatric population, which is 1.27 +/- 0.67 mm. We are reporting a baby of seven months who presented with conjugated hypebilirubinemia and pancreatitis due to Round Worm in CBD. [ABSTRACT FROM AUTHOR]

The IEEE 1584 Guide does not address arc-flash hazard in dc systems. The interest in this subject is evidenced by current publications. The National Fire Protection Association (NFPA) 2012 methodology has added a small description of the calculations of arc-flash hazard in dc systems. However, there are serious inaccuracies in the application of the methodology that is advocated in the NFPA. A review of the current literature indicates that there is no comprehensive document on the subject and that some of the assumptions made in the current literature are not accurate, e.g., with respect to the short-circuit current profiles and protective devices in dc systems, which are very fundamental to the accurate calculations of arc-flash hazard in dc systems. This paper is presented in two parts. This part provides equations with practical examples of short-circuit calculations in dc systems. The second part provides the analysis of arc-flash hazard. Accurate calculations of the short-circuit currents and ascertaining their profiles is the first step in the arc-flash hazard analysis. [ABSTRACT FROM PUBLISHER]

Based on the results of the short-circuit calculations in Part I of this paper, the calculation of the arc-flash hazard in dc systems is demonstrated. Much like ac systems, the arcing currents are not the same as the short-circuit currents. The National Fire Protection Association 2012 methodology recommends that the arcing current be taken as 50 $\%$ of the calculated dc short-circuit current and that the arc-flash hazard be calculated for a time duration of 2 s. Both these concepts are much flawed and will give inaccurate results. It is also imperative to appreciate the short-circuit protection in dc systems. Semiconductor devices have very little energy let-through withstand capability and are protected with fast-acting semiconductor fuses or dc circuit breakers that may arrest the prospective short-circuit current and limit the incident energy release to a small value. This paper calculates the arc-flash hazard in specimen cases to demonstrate the methodology of the calculations in low-voltage and medium-voltage dc systems. [ABSTRACT FROM PUBLISHER]

Highlights: [•] Effect of Sn on the indentation size effect in Ti–Fe–(Sn) has been explored. [•] Fitting through ISE models point the existence of strain gradient beneath indenter. [•] Correlation has been established between dislocation density, grain size and ISE. [•] ISE in Ti–Fe–Sn ultrafine composites requires a dislocation density of ∼1014–1016/m2. [Copyright &y& Elsevier]

Mobile hydraulic machines are used in various operations like construction, material handling and mining. High powers to weight ratio and manoeuvrability in rough terrains are striking features that help in edging out their electrical and mechanical counterparts. Internal leakage in hydraulic actuators is a faulty condition frequently observed in hydraulic machines. Internal leakage in the actuator affects the system's dynamic performance and decreases its energy efficiency. Also, internal leakage is apparent only when the leakage is extreme and the actuator stops responding to command signals. Thus, detecting internal leakage in its early stages is a difficult task. Early detection and corrective action save energy, reduce component degradation, and reduce machine downtime. There are many existing techniques for internal leakage detection of hydraulic actuators, but they are intended for actuators working in a laboratory environment. The main focus of this paper is to present a practical method for early detection of internal leakage fault present in boom actuator of mobile hydraulic machines by analysing the machine work-cycle data with minimum hardware. The method trains and validates a Support Vector Machine (SVM) classifier using pressure and boom angle displacement signals. The time-series signals are processed using 'event-based' feature extraction method. The binary version of Particle Swarm Optimisation is used for feature selection. The trained classifier can detect and classify internal leakage faults with more than 95% accuracy, which is sufficient for taking appropriate preventive maintenance steps on time. • A method for early detection of internal leakage in hydraulic excavator is presented. • Feature extraction from actuator pressure and boom angle displacement signals. • Feature selection using Binary particle swarm optimisation from the feature space. • Fault detection and classification is done using Support Vector Machine classifier. • Proposed method can be used for Condition Based Maintenance of hydraulic actuator. [ABSTRACT FROM AUTHOR]

The 13.8-kV selective high-resistance grounding (HRG) systems for bus-connected generators are nonexistent due to two reasons: One is that the stray capacitance current of the system can be high (> 10–12 A), and the other is that the sensitivity and selectivity of the ground-fault devices to detect low levels of ground-fault currents are required. This paper describes the relay types, sensors, settings on protective relays, and flow of currents for various fault locations in a 13.8-kV system and demonstrates how a selective HRG has been implemented. To the authors' knowledge, there is no HRG selective system at 13.8 kV. [ABSTRACT FROM PUBLISHER]

Abstract: The transient stage during isothermal oxidation of Mo76Si14B10 has been studied at 1150°C. The maximum mass loss is found to occur by volatilization of MoO3 within the first 480s of exposure, which is considered to be the transient period. Scanning electron microscopic studies have revealed that a glassy borosilicate layer flows to cover the top surface, and thereby it acts as a protective coating. The thickness of the borosilicate layer increases with exposure time following a parabolic relationship. The mechanism of oxidation during transient period has been discussed with the help of an analytical model. [Copyright &y& Elsevier]

- Neon was measured in 39 individual olivine (or olivine-rich) grains separated from individual chondrules from Dhajala, Bjurböle, Chainpur, Murchison, and Parsa chondrites with spallation-produced 21Ne the result of interaction of energetic particle irradiation. The apparent 21Ne cosmic ray exposure (CRE) ages of most grains are similar to those of the matrix with the exception of three grains from Dhajala and single grains from Bjurböle and Chainpur, which show excesses, reflecting exposure to energetic particles prior to final compaction of the object. Among these five grains, one from chondrule BJ2A5 of Bjurböle shows an apparent excess exposure age of approximately 20 Ma and the other four from Dhajala and Chainpur have apparent excesses, described as an 'age,' from 2 to 17 Ma. The precompaction irradiation effects of grains from chondrules do not appear to be different from the effects seen in olivine grains extracted from the matrix of CM chondrites. As was the case for the matrix grains, there appears to be insufficient time for this precompaction irradiation by the contemporary particle sources. The apparent variations within single chondrules appear to constrain precompaction irradiation effects to irradiation by lower energy solar particles, rather than galactic cosmic rays, supporting the conclusion derived from the precompaction irradiation effects in CM matrix grains, but for totally different reasons. This observation is consistent with Chandra X-Ray Observatory data for young low-mass stars, which suggest that our own Sun may have been 105 times more active in an early naked T-Tauri phase (Feigelson et al. 2002). [ABSTRACT FROM AUTHOR]

Abstract: The effect of superficial CeO2 coating on the oxidation behavior of Ti–6Al–4V has been studied under isothermal and cyclic heating conditions in the temperature range of 923–1223K in dry air. During the early periods of exposure, the oxide scale grows obeying near linear followed by near parabolic kinetics and consists of alternate layers of α-Al2O3 and TiO2. The mass gain of the uncoated alloys is found to be two times higher than that of the coated one in the temperature range of 923–1123K up to 36h of exposure. The scale composition on the bare or coated alloy is found to depend both on the temperature and on the time of exposure. During cyclic exposure, the scale suffers spallation for both the bare and the coated alloy, which has been attributed to insufficient plasticity of the scale. [Copyright &y& Elsevier]

When supplementation of oxygen is inappropriate there is chance of development of either hypoxia or hyperoxia. During oxygen therapy, oxygen level should be maintained within a target-able range through proper monitoring. Pulse oximetry is a useful convenient and reliable monitoring system. The principle of working of pulse oximeter is based on the fact that oxyhaemoglobin and deoxyhaemoglobin absorb light at the red end of the spectrum differently; Deoxyhaemoglobin absorbs more red than infrared and oxyhaemoglobin more infrared than red. The 'emitter' of the probe of pulse oximeter sends equal intensities of red and infrared light into the tissue. The 'sensor' detects the ratio of red to infrared that emerges. From this information the proportion of oxyhaemoglobin to deoxyhaemoglobinthat is, the percentage saturation of hemoglobin with oxygen is calculated and displayed to the monitor of the instrument. The main advantage of pulse oximeter is that it is noninvasive, less complex, does not require calibration, provides continuous measurement of hemoglobin-oxygen saturation (SpO2), fast response time and high accuracy. Limitations of accuracy of pulse oximetry lie on poor perfusion, hypoxic events, hyperemia, severe anemia, dyshemoglobinemias, high oxygen partial pressures (PaO2), superficial pigments, black skin of infant, motion artifact, pressure on sensor, presence of abnormal dye, light and electrical interference. It is essential to remember the limitations of this instrument before going to pulse oximetry. [ABSTRACT FROM AUTHOR]

Abstract: A clean signature of room temperature multiferroicity in Bi1.2Gd0.1Fe0.8O3 ceramics is observed. Samples were prepared by slow step sintering technique at 850°C. Impurity peaks normally present in original BiFeO3 are completely suppressed with the increase of Bi concentration. Apart from this, structural transformation took place from R3 C to Pn21 a space group and a clear orthorhombic grain growth habit is seen by SEM microstructure. Suppression of impurity phases favors the reduction of mobile oxygen vacancies and hence reduces leakage current for which ferroelectric properties of Bi1.2Gd0.1Fe0.8O3 are enhanced. We argue that the addition of Gd is likely to suppress the spiral spin modulation and at the same time increase the canting angle which favors the enhanced ferromagnetism. Excess Bi is expected to act as point defects and occupy interstitial positions which in turn surrounded by oxygen vacancies and is likely to promote defect driven ferromagnetism with enhanced spin and electric polarization. This finding encourages further revaluation of long-discounted BiFeO3 for multiferroics research. [ABSTRACT FROM AUTHOR]

This paper demonstrates that, in a multi-voltage-level (medium and low voltages) distribution system, the incident energy can be reduced to 8 \cal/\cm^2 (hazard risk category 2) or even less, so that a personal protective equipment outfit of greater than two is not required. This is achieved with the current state-of-the-art equipment and protective devices. It is recognized that, in the existing distribution systems, not specifically designed with this objective, it may not be possible to reduce the arc-Flash hazard to this low level, unless major changes in the system design and protection are made. A typical industrial distribution system is analyzed, and tables and time-coordination plots are provided to support the analysis. Unit protection schemes and practical guidelines for arc-Flash reduction are provided. The methodology of IEEE 1584 is used for the analyses. Reducing HRC also reduces the fault damage to the equipment. [ABSTRACT FROM AUTHOR]

The industry is heading toward innovations in the electrical system designs, equipment, and protection to limit the arc flash hazard. This paper demonstrates that, in a multi-voltage-level (medium and low voltages) distribution system, the incident energy can be reduced to 8 \cal/cm^2 or even less [hazard risk category 2] so that a personal protective equipment outfit that is greater than two is not required. This can be achieved with the current state-of-the-art equipment and protective devices. This paper has two parts: part 1 is for the methodology, and part 2 is for the analysis. There are variations in the calculation results, depending upon the calculation methods. A new method for the calculation of the energy accumulation to account for the decaying nature of the short-circuit currents is presented. [ABSTRACT FROM AUTHOR]

Abstract: A comparative study has been carried out to investigate the effects of Al and/or Ce additions on microstructure of Mo–Si–B alloys and their isothermal oxidation behaviour at 500 and 700 °C in laboratory air for 24 h. Microstructure of arc melted Mo–Si–B–(Al, Ce) alloys consists of bcc α-Mo dendrites embedded in ultrafine lamellar Mo3Si and Mo5SiB2 eutectic matrix. Isothermal oxidation kinetics of ultrafine structured Mo–Si–B alloy at 500 °C has been found to show hardly any mass change during 24 h exposure. Addition of Al to Mo–Si–B alloy refines the microstructure, decreases the net mass loss at 700 °C by ∼43%, whereas Ce does not bring about any significant change. The enhanced oxidation resistance of Mo–Si–B–Al alloy is due to the formation of Al–O rich inter-layer at the alloy/oxide interface along with the formation of a protective and dense Al2(MoO4)3 outer layer, which reduces the sublimation of MoO3 at 700 °C. Various transient/complex oxides formed on the alloys during their high temperature exposure have been examined to determine the oxidation mechanisms. [ABSTRACT FROM AUTHOR]

Abstract: Mechanical prehistory is an important factor on the stability of the structure, and consideration of this issue is also useful for determining the mechanisms of post-deformation and fracture processes in bulk metallic glasses. We present investigations to reveal the effect of prestraining on the compressive deformation, morphology of the fracture surface and the evolution of microstructural inhomogeneity in Zr44Ti11Cu9.8Ni10.2Be25 (Vitreloy 1b) “brittle” bulk metallic glass (BMG). The intrinsic plasticity of the BMG increases linearly from 0.7% up to 15% plastic strain upon cold rolling up to 30% prestrain at room temperature due to the change of the short-range order of the glassy phase. Regions of river-like patterns appeared on the fracture surface of prestrained BMGs after compression test, which is similar to that appear during tensile deformation indicating the development of a deformation-induced inhomogeneous residual stress distribution. The effect of uniaxial cyclic compression on the flow stress of the as-cast BMG is also investigated. [ABSTRACT FROM AUTHOR]

Abstract: Ultrafine structured Ti70.5Fe29.5 and Ti67.79Fe28.36Sn3.85 eutectic rods comprising of β-Ti and TiFe phases were prepared by copper mould casting. The corrosion and passivation behaviour were investigated in halide free aqueous media (pH 1–13) by means of potentiodynamic polarisation and potentiostatic current transient measurements. Both eutectic alloys exhibit excellent corrosion resistance due to spontaneous passivation. The passive film compositions grown several nanometres on single phase polycrystalline specimens were analyzed with Auger electron spectroscopy. They consist of oxidized Ti and Fe species. Layers grown in strongly acidic environment are depleted in Fe. Sn was detected only on layers grown on the constituent β-Ti phase and only in the metallic state. The pitting susceptibility was investigated in strongly acidic media (pH≤1) containing 0.1–3M of chloride ions. The Sn-containing eutectic alloy was found to be more susceptible to pitting corrosion. [Copyright &y& Elsevier]

Abstract: The critical micelle concentration (cmc) of TX-100 in formamide (FA) was determined from surface tension measurements as functions of temperature and NaCl concentration. At 25°C, cmc was also determined by the fluorescence method. For the sake of comparison, micellization parameters of TX-100 were also determined in water. cmc, aggregation number, and standard free energy of micellization in FA are about 400 times higher, 10 times lower, and 2 times higher than in water, respectively. On increasing the temperature, cmc in FA shows a slight increase, whereas in water it decreases. The logarithm of relative cmc decreases linearly with added NaCl concentration in both FA and water, and the rate of this decrease is surprisingly equal in the two solvents. Micellization of TX-100 is exothermic in FA, but endothermic in water. The cloud point (CP) of TX-100 was determined in FA+water medium and that in pure FA was estimated to be ∼233°C when [TX-100]=0.15molkg−1. Surface excess values of TX-100 were calculated from Gibbs and Langmuir adsorption isotherms. Values of standard free energy of adsorption calculated from the Rosen–Aronson equation and from the Langmuir adsorption isotherm are comparable. The ratio of the surface tension of the solvent to that at the cmc has been demonstrated as a novel scale for measuring solvophobicity. [Copyright &y& Elsevier]

Abstract: The effect of Al content on the glass formation and mechanical properties was studied for (Cu50Zr50)100−x Al x (x =0, 4, 5, 7) bulk metallic glasses. The crystallization temperatures of fully amorphous Cu50Zr50, Cu48Zr48Al4, Cu47.5Zr47.5Al5 and Cu46.5Zr46.5Al7 as-cast rods are 724K, 753K, 758K and 782K, respectively. The mechanical properties were investigated under compression at room temperature. As-cast Cu46.5Zr46.5Al7 shows the highest yield strength (1867MPa), whereas Cu47.5Zr47.5Al5 shows the largest fracture strain of 11.2%. The fracture surfaces of the compressed samples were investigated by scanning electron microscopy and their morphology has been correlated with the compressive plasticity. [Copyright &y& Elsevier]

Abstract: To circumvent the limited plasticity of bulk metallic glasses (BMGs), heterogeneous materials with glassy matrix and different type and length-scale of heterogeneities (micrometer-sized second phase particles or fibers, nanocrystals in a glassy matrix, phase separated regions, variations in short-range order by clustering) have been reported. We developed bulk metallic glasses and glass matrix composites in martensitic Zr–Cu-base alloys. Large plasticity can be obtained from microstructure consisting of either a glassy structure, or for alloys with martensitic second phase embedded in a glassy matrix. This type of glasses and glass–matrix composites are able to achieve high strength together with pronounced work-hardening. We explore the possibilities to synthesize such in situ composite microstructures based on shape memory alloys (“M-Glasses”) through metal mold casting. [Copyright &y& Elsevier]

Abstract: In the present study we investigate the phase formation and the thermal stability of Cu50Zr50− x Ti x (0≤ x ≤10) and (Cu0.5Zr0.5)100− x Al x glass-forming alloys. Parameters indicating the glass-forming ability (GFA) are calculated from isochronal and isothermal calorimetric experiments. A high Ti content in the Cu–Zr–Ti alloys causes the precipitation of a metastable ternary Laves phase (C15), which does not form in Cu–Zr–Al. Accompanied with it is a significant drop in the activation energy of crystallization. Also the supercooled liquid region (ΔT x = T x − T g), the reduced glass transition temperature (T rg = T g/T liq), and the γ parameter (γ = T x/(T g + T liq)) (T x: crystallization temperature, T g: glass transition temperature and T liq: liquidus temperature) are sensitive to the change in the crystallization sequence. The fragility values calculated are believed to overestimate the GFA of the investigated alloys. Careful selection of the alloy composition enables the targeted precipitation of different crystalline phases. [Copyright &y& Elsevier]

The interrupting duty of high-voltage circuit breakers can be reduced by increasing the contact parting time, which is the sum of tripping delay and the circuit breaker opening time. The contact parting time is fixed; however, the tripping delay can be increased. Although this method is not discussed in current technical literature, it is valid according to the ANSI/IEEE standards. Immediate replacement of the circuit breakers or other alternatives to reduce interrupting duties can be avoided, resulting in large cost savings and process downtime. The problem occurred in a large paper mill distribution system, where the circuit breakers were applied well within their close and latch ratings but the interrupting duty exceeded by 6%. By introducing an additional tripping delay of one cycle, the interrupting duty is reduced and the existing breakers are retained in service. This paper demonstrates these calculations. [ABSTRACT FROM AUTHOR]

Abstract: An arc-melted Zr73.5Nb9Cu7Ni1Al9.5 alloy consists of dendritic body-centered cubic solid solution and a mixture of ultrafine body-centered tetragonal Zr2Cu-type and hexagonal close-packed MgZn2-type phases in the ultrafine matrix. This composite exhibits two exothermic reactions upon heating to 973K with a heating rate of 40K/min. After the first exothermic reaction nano-scale ω-phase particles have formed in the β-phase dendrites indicating a decomposition of the supersaturated solid solution upon heating. At the early stage during the decomposition of the β-phase the ω-phase is coherent with the parent phase without clear structural differences. However, semicoherency between the β- and the nano-scale ω-phase regions was observed during the growth of the ω-phase. This structural semicoherency causes nano-scale twinning in the β-phase dendrites around the ordered ω-phase in order to release the mismatch energy at the interfaces between the ordered ω- and β-phases. [Copyright &y& Elsevier]

Abstract: Mg–Fe–CO3 layered double hydroxide (LDH) with a Mg/Fe molar ratio of 2.0 was synthesized by co-precipitation method and its calcined product (CLDH) was obtained by heating Mg/Fe-LDH at 500 °C. Sorption of SeO2− 3 on CLDHs was studied and the results indicate that the sorption capacity of CLDHs was higher than that of uncalcined LDHs. Isotherms for SeO2− 3 sorption by CLDHs were well described using the Freundlich and Langmuir equations. The thermodynamic parameters, viz. , , were calculated to predict the nature of adsorption. The negative and positive values of and indicate that the adsorption process is spontaneous and endothermic in nature, respectively. The adsorption process followed first-order kinetics. [Copyright &y& Elsevier]

Abstract: Investigation of the microstructure of a compressed Ti66.1Cu8Ni4.8Sn7.2Nb13.9 nanostructure–dendrite composite reveals that the deformed bcc β-Ti dendrites form a stepped morphology at the interfaces between the individual dendrites and the nanostructured matrix of hcp α-Ti and bct Ti2Cu phases. Furthermore, there is a unique stained contrast during the propagation and the interaction of the shear bands in the dendrites indicating a local structural change near to the apex of the shear bands in the dendrite. In contrast, the shear bands pass through coherent grain boundaries between the hcp α-Ti and the bct Ti2Cu phases of the nanostructured matrix. [Copyright &y& Elsevier]

Abstract: An ultra-fine eutectic structure has been obtained in the Ti70.5Fe29.5 binary alloy by slow cooling from the melt through arc melting and cold crucible rod casting. The addition of 3.85 at.% Sn to the binary Ti–Fe alloy induces a change of the morphology of the eutectic and increases the volume fraction of the FeTi (Pm3m) phase. A significant improvement of the plastic deformability of the ternary alloy has been observed under uniaxial compressive loading resulting in 16% strain to failure compared to 3.4% for binary Ti70.5Fe29.5. The morphology of the eutectic colonies, their refinement and supersaturation of the β-Ti phase are crucial factors for improving the ductility of the ultra-fine eutectic alloys. [Copyright &y& Elsevier]

Abstract: The deformation behavior of multicomponent Ti66Cu8Ni4.8Sn7.2Nb14 composite containing primary dendrites embedded in a nanoeutectic matrix was studied under uniaxial compression. The evolution of slip and shear bands has been investigated at various stages of deformation. This type of advanced composite not only displays a high compressive plasticity of 31.8%, but also exhibits high fracture strength of ≈2.02GPa (true fracture strength 1.38GPa). Pronounced work hardening was observed after yielding. The surface deformation morphology reveals that the work hardening behavior of the composite is related to the plastic deformation of the dendritic phase through slip bands and the interaction of shear bands in the nanostructured matrix with the hardened dendrites. The nucleation of shear band occurs at a certain amount (8%) of plastic deformation at the dendrite–nanoeutectic matrix interface. The final stage of compression proceeds through passing of the shear bands through the work-hardened dendrites into the nanoeutectic matrix, whereby the propagation of the shear bands in the matrix is retarded by the nanoscale phases. [Copyright &y& Elsevier]

This paper is based on modifications implemented in the protection and grounding systems of a large paper mill and describes selective ground fault protection for a 13.8-kV system with multiple bus-connected generators, synchronous bus ties, and utility interconnections. The ground fault current in the system is reduced from the existing 3400 A to 500 A, and a hybrid grounding system is implemented for each of the generators. As the ground fault currents are reduced to limit the fault damage, the sensitivity and selectivity of the ground fault protection become important. Directional ground fault relays with coordinating pickup settings are applied to achieve this objective. The new platform for directional elements (numerical relays) drives its performance from sequence impedance measurements. [ABSTRACT FROM AUTHOR]

Abstract: Heteropoly acids (molybdophosphoric acid and tungstophosphoric acid) of different wt.% (5–20wt.%) were intercalated in Zn–Al hydrotalcite-like-compounds by indirect intercalation via terephthalate route and the materials were characterized by PXRD, FTIR, BET, acid sites, etc. PXRD reveals intercalation of MPA and TPA species, which is further corroborated by the presence of these Keggin ions by FTIR. The catalytic activity of the prepared catalysts was tested for the liquid phase esterification of acetic acid using n-butanol under autogenous condition. The effect of various reaction parameters such as molar ratio of the reactants, temperature, time and catalyst dose, etc. on the conversion of acetic acid was studied and the findings are discussed. The 15wt.% MPA intercalated sample shows highest conversion (84.15%) with 100% selectivity for n-butyl acetate. [Copyright &y& Elsevier]

Abstract: Hydrotalcite-like compounds (HTlcs) containing Mg2+, Al3+, and Ce3+ in the hydroxide layer and with carbonate as charge-balancing anion have been prepared by a co-precipitation (at constant pH) method. The Al/Ce ratio in the final product depends on the concentration in the initial solution. The crystallinity of the layered materials decreases with the increase in cerium content, probably, due to the distortions introduced by the large difference in the ionic radii of the cations. All the synthesized materials were characterized by XRD, FT-IR spectroscopy and TG/DTA. The textural properties were determined from low-temperature nitrogen adsorption–desorption measurements. [Copyright &y& Elsevier]

Abstract: Systematic investigations of the microstructural changes upon compression have been performed in order to elucidate the microscopic deformation mechanisms of the high-strength and ductile Ti66.1Nb13.9Ni4.8Cu8Sn7.2 nanostructure–dendrite composite. After 8% deformation, a rotation of β-Ti dendrites is observed during the interaction of slip and shear bands. This rotation leads to the formation of new slip bands in the dendrites. The β-Ti dendrites locally transform into ω phase during the interaction between the newly and the previously formed slip bands. The rotation of the dendrites causes local volume changes at the interfacial areas between the dendrites and the matrix, consisting of a mixture of hexagonal close-packed α-Ti and body-centered tetragonal Ti2Cu phases. This induces a rotational stress into the nanostructured matrix. After further deformation up to 25%, the shear bands penetrate the dendrite/matrix interfaces, producing extra interfaces. The nanostructured matrix exhibits a sandwiched microstructure in order to accommodate effectively the shear strains. These results suggest that structural coherency of the dendrite/matrix interfaces is important for controlling both the strength and the ductility of the nanostructure–dendrite composite. [Copyright &y& Elsevier]

Abstract: Usually, bulk metallic glasses exhibit strength values superior to conventional crystalline alloys, often combined with a large elastic limit and rather low Young''s modulus. This combination of properties renders such alloys quite unique when compared to commercial materials. However, the major drawback for engineering applications is their limited room temperature ductility and toughness due to the localized deformation processes linked to shear banding, where high plastic deformation is accumulated in a very narrow region without contributing to macroscopic deformation, work hardening or yielding. In this work we report on a new class of metallic glass in a simple Cu-base alloy. Addition of 5at.% Al increases the glass-forming ability of binary Cu50Zr50. The resulting Cu47.5Zr47.5Al5 glass exhibits high strength (2265MPa) together with large room temperature ductility up to 18%. After yielding a strong increase in the flow stress is observed during deformation. The structure of the metallic glass exhibits atomic-scale heterogeneities that enable easy nucleation and continuous multiplication of shear bands. The interaction and intersection of shear bands increases the flow stress of the material with further deformation, leading to a ‘work hardening’-like behavior and yields a continuous rotation of the shear angle up to fracture resulting in a high compressive ductility. [Copyright &y& Elsevier]