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Insulin degludec (degludec) is a second-generation basal insulin with an improved pharmacokinetic–pharmacodynamic profile compared with first-generation basal insulins, but there are few data regarding its use during pregnancy. In this non-inferiority trial, we aimed to compare the efficacy and safety of degludec with insulin detemir (detemir), both in combination with insulin aspart (aspart), in pregnant women with type 1 diabetes.

This paper proposes a state feedback output tracking Model Reference Adaptive Control (MRAC) to control the power of a nuclear reactor. A linearized version of nuclear reactor dynamics based on point kinetics modeling, with parameter uncertainties, is utilized for the control studies. Normalized negative gradient algorithm is used to update the controller gains adaptively. Stability of the closed loop system is established through Lyapunov analysis and Barbalet’s lemma. Performance of controller is validated through non linear simulation studies.

The steady-state visually evoked potential (SSVEP) based brain-computer interfaces (BCIs) generally deploy flickering stimuli with different frequencies in order to generate different commands. This paper presents a setup that can be used to generate multiple commands from a single flickering stimulus using magnitude modulation of SSVEP through eye-accommodation. In this setup, a flickering stimulus was shown on the computer screen and a passive fixation target was placed between the screen and the subject. The eye-accommodation mechanism to focus on the target between the screen and the subject, caused the flickering stimulus to become blurred which reduced the magnitude of the evoked SSVEP response. The reduced magnitude SSVEP response can be used to generate another command over the command generated when the subject focuses directly on the stimulus. The fixation target was placed at 3 different positions that can provide up to 4 commands from the single flicker stimulus. Fifteen healthy human subjects participated in the experiments. The mean offline accuracies obtained for 2-class, 3-class, and 4-class extraction were 100%, 94.2 ± 6.1%, and 80.9 ± 9.7% respectively for a 4-seconds time window.

ABSTRACTThe need of vehicular license plate recognition system (VLPR) has arisen based on the need to implement traffic control on transportation systems, since early 1970s. Since then, researchers are continuously proposing various approaches and solutions. One of the significant and challenging tasks is to localize the license plate of the moving car. Since the license plate standards are not strictly practiced in world, a large amount of variations are obtained like, size, location, type of font used, background and foreground colour, and so on. The principal component analysis (PCA) is one of the widely used and most successful techniques that have been used in image recognition and compression. In this paper, we propose a novel approach to identify the license plate using PCA.

The objective of this work was to assess the impact of deviations from isothermality in packed bed and coated wall membrane reactors on the rates of HI decomposition. A two-dimensional modelling was done for a packed bed membrane reactor as well as a coated wall membrane reactor for HI decomposition. The smaller diameter reactor showed higher apparent catalyst activity. The reactivity results showed that the reactors suffered from significant temperature gradients. We estimated the diameter required for packed bed and coated wall membrane reactors to achieve near isothermal operation. The coated wall reactor gives lower conversion than the packed bed reactor. The model confirmed that the measured catalyst activities in different diameter reactors varied due to heat transfer and pressure drop effects.

AbstractFuel used in nuclear reactors contains fissile material. The fission process releases a huge amount of energy, and hence, the fissioning components must be held in a robust form capable of enduring high operating temperatures and an intense radiation environment. The shape and integrity of the fuel structures must be maintained over a period of several years within the reactor core to prevent the leakage of fission products into the reactor coolant. Further, the fuel rods must be in a nondistorted state for proper alignment in the fuel assembly to ensure proper fuel bundle power distribution. Improper core power distribution can breach the safety and operational limits on fuel and channel powers. The strategy discussed includes the methodology to verify the fuel assembly using image processing techniques. The methodology uses the Radon transform and contains four phases: image reading, preprocessing, Radon transform, and verification. The approach has been validated on 1026 fuel assemblies of a nuclear power plant, for which experimental results are shown.

Global warming and climate change necessitate a serious move away from fossil–based systems toward hydrogen economy. A study has been carried out on different thermochemical cycles for hydrogen production to bring about their important aspects. The study involves process description of different routes followed by thermochemical cycles. These include metal oxide processes, sulphur family processes like iodine sulphur cycle and Westinghouse cycle, halide family processes like UT–3 and Ispra Mark cycle, copper chlorine cycle and others. This paper gives an insight into the advantages and disadvantages associated with the processes. The review is done keeping in view the relevant and useful aspects in research to present information in terms of species, operating parameters, reactors, costs involved, safety, etc. This will provide a platform for further research to save effort by referring the basic information on thermochemical cycles, so that an appropriate and satisfactory cycle may be chosen.

Nanotechnology is a potential augmentation to the existing water purification technologies. Four different types of functional nanomaterials, like carbon nanotubes, metal/metal oxide nanoparticles, dendrimers and zeolites, are currently under evaluation for water purification application. Nanomaterials offer excellent opportunities because of high surface area (surface/ volume ratio), but the challenge is to build up an integrated scalable system. Membranes, because of being energy-economic and having the ability to get associated to different processes as a pretreatment or post-treatment stage, fi nd tremendous applications in the field of water purification. Nanostructured materials serve as a wonderful tool towards development of high flux, high selective membranes. Here attempts are made to develop biofouling resistant membrane. Nanoparticles of silver, copper and silver–copper mixture were impregnated on to the polysulfone host matrix and the biofouling resistance behavior of each membrane surface was examined. The performance of the membranes was evaluated in terms of pure water permeability and solute rejection studies. The membranes were characterized using scanning electron microscopy, energy dispersive X-ray, water contact angle and atomic force microscopy studies. The authors conclude that the silver impregnated membranes possess the best biofouling resistant behavior. The present paper discusses the potential of nanoparticles for water purifi cation and explains briefly the R&D work carried out in the research centre towards development of a biofouling resistant nanocomposite membrane.

Nanotechnology is a potential augmentation to the existing water purification technologies. Four different types of functional nanomaterials, like carbon nanotubes, metal/metal oxide nanoparticles, dendrimers and zeolites, are currently under evaluation for water purification application. Nanomaterials offer excellent opportunities because of high surface area (surface/ volume ratio), but the challenge is to build up an integrated scalable system. Membranes, because of being energy-economic and having the ability to get associated to different processes as a pretreatment or post-treatment stage, fi nd tremendous applications in the field of water purification. Nanostructured materials serve as a wonderful tool towards development of high flux, high selective membranes. Here attempts are made to develop biofouling resistant membrane. Nanoparticles of silver, copper and silver–copper mixture were impregnated on to the polysulfone host matrix and the biofouling resistance behavior of each membrane surface was examined. The performance of the membranes was evaluated in terms of pure water permeability and solute rejection studies. The membranes were characterized using scanning electron microscopy, energy dispersive X-ray, water contact angle and atomic force microscopy studies. The authors conclude that the silver impregnated membranes possess the best biofouling resistant behavior. The present paper discusses the potential of nanoparticles for water purifi cation and explains briefly the R&D work carried out in the research centre towards development of a biofouling resistant nanocomposite membrane.

Careful optimisation of a safe and sustainable route for hydrogen production is a pressing need. Thermochemical processes employing water as raw material and nuclear/renewable energies as energy source are believed to be the best possible option in this direction, while alarming issues such as climate change and global warming are being taken into account. Amongst the well-identified cycles, the sulphur-iodine (S-I) thermochemical route assumes the highest thermal efficiency and the best one as regards its coupling to a high temperature nuclear reactor. Material development is the key issue to be addressed to realise successfully the potential of the S-I cycle. The most important area is development of gas-permeable membranes for enhancement of the equilibrium decomposition of HI, which is the most intricate step as far as the overall process efficiency is concerned. In order to overcome the low efficiency associated with the low equilibrium decomposition of HI, the authors intend to develop a hydrogen permselective membrane reactor. As a first step towards this development, a silica membrane of asymmetric nature was developed using sol-gel processing and dip coating, and characterised using scanning electron microscopy and a BET surface area analyser. A road map towards realising the successful emergence of the membrane reactor is discussed.

We report the fabrication of a hybrid all semiconductor core/shell nanotetrapod structure consisting of crystalline ZnS:Mn core and amorphous Si shell for the first time. The nanostructures were produced via a catalyst-free rapid thermal evaporation technique. Core/shell nanotetrapods were formed in two steps: (i) formation of the crystalline ZnS:Mn tetrapods and (ii) simultaneous surface adsorption of the in situ formed Si vapor species providing the amorphous shell. Crystalline tetrapod formation was guided by the formation of cubic structured ZnS octahedrons with four active (111) polar growth planes, which served as the favored growth site for the four wurtzite structured legs of the tetrapods. Choice of chloride salt as the source of dopant ion was crucial for the in situ generation of Si vapor. At elevated temperature, chloride salt reacted with the sulfur vapor to produce S2Cl2gas that etched the Si wafers, generating Si vapor. Suppression of the surface-state-related blue emission was observed in the core/shell structures that clearly supported the formation of a shell layer. Elimination of the surface states ensured efficient energy transfer to the dopant Mn ionic state, resulting in the strong orange emission via 4T1−6A1electronic transition.

A simple strategy for detection of glutathione (GSH) in physiologically relevant concentrations is reported by manipulating the electron transfer pathways of surface-modified quantum dots. The probe consisted of fluorescent CdS:Mn/ZnS core/shell quantum dots (Qdot) properly conjugated to dopamine through CS2-assisted zero-length covalent coupling. Qdots exhibited bright yellow-orange emission at ∼ 592 nm, which could be attributed to the 4T1→6A1transition of Mn2+ions in Qdot core. The fluorescently dark Qdots (OFF state) was obtained by modifying the Qdot surface with an electron rich dopamine molecule. The fluorescence of the probe was restored (ON state) when the disulfide bond was cleaved by the reducing GSH.

Direct room temperature synthesis of ultrasmall (2.5 ± 0.2 nm), water dispersible ceria nanoparticles are reported for the first time. Nanoparticles were synthesized directly in ethylenediamine that served as a catalyst as well as capping agent. Larger particles could be obtained by solvothermal synthesis keeping other parameters identical. X-ray photoelectron spectroscopic studies indicated the formation of valence state engineered (a mixed valence state of Ce3+and Ce4+) ceria nanoparticles. The proportion of the valence states could be tuned by varying the solvothermal synthesis temperature and solvent composition by introducing water along with ethylenediamine. UV−visible transmission studies revealed antioxidant properties of the nanoparticles that could lead to possible therapeutic applications of the nanoparticles in biomedicine. It was observed that the ultra small ceria nanoparticles having mixed valence state prevent photobleaching of organic dyes by scavenging free radicals.

Bipyramidal-shaped single crystalline nanocones of ZnO, doped with Mn2+ions up to different concentrations, were synthesized through a solvothermal route and characterized by X-ray diffraction and transmission electron microscopy. The compositional analysis was also carried out by energy-dispersive analysis of X-rays (EDAX). Positron annihilation studies were carried out to extract information on the vacancy-type defect clusters and their evolution under doping, which may have a major influence on the physical properties of the material. In the undoped ZnO, trivacancy-type defects of the type VZn+O+Znare present. Doping by Mn2+ions reduced them to divacancies (VZn+O) as a result of the ion-vacancy complex formation. These were indicated by the measured positron lifetimes and coincidence Doppler broadening measurements. An interesting observation is the reduction in base diameters of the nanocones at high (>1 atom %) dopant concentrations, an effect of increased strain due to occupancy of Zn2+vacancy sites by Mn2+ions of slightly larger radius. As the diameters of the grains reduce to below the thermal diffusion lengths of positrons, significant number of annihilation events seemed to result from the surfaces of the nanocones. The intercrystalline regions also gave a favorable site for the formation and “pick-off” annihilation of orthopositronium atoms.

High-aspect ratio Cd1−xZnxS (x= 0−1) alloy semiconductor nanowires are reported here for the first time using an ethylenediamine (en)-assisted solvothermal approach. The composition of the en−water (en-w) mixed solvent plays a crucial role in determining the morphology and crystalline phase of the alloy nanowires in the middle range of x(i.e., when xapproaches 0.5). A phase transformation from hexagonal to cubic was observed for the middle range of xin an en-dominated solvent (en/w, 5:1). Nanowires with hexagonal phases were formed for the entire range of xwith increasing water content of the solvent system (en/w, 2:1). The aspect ratio of the nanowires was found to be dependent on the xvalue as well as solvent composition. Alloy nanowires exhibit photoresponse properties when illuminated under white light. The synthesis technique is modified to synthesize core−shell Cd1−xZnxS/ZnS nanowires. Enhancement in photoluminescence efficiency is observed with a ZnS shell over the alloy nanowires.

Metal/semiconductor core/shell radial heterostructured coaxial nanowires are reported for the first time. The radial coaxial nanowires consisted of a crystalline metallic Ag core and semiconducting amorphous Si shell. The Ag core nanowire growth was guided by the gold-catalyst-assisted vapor−liquid−solid process, whereas the amorphous Si shell formation could be attributed to the surface diffusion of the Si species through the liquid Au droplets to the nanowire surface.

Mn-doped ZnS nanorods synthesized on zinc foils by a solvothermal approach exhibited white light emission upon excitation in the UV range (300−330 nm). X-ray diffraction studies coupled with energy-dispersive X-ray analysis and X-ray photoelectron spectroscopy indicated the presence of a thin oxide layer on the Mn-doped ZnS nanorods. The diameters and lengths of the nanorods varied within the ranges 5−12 and 50−100 nm, respectively. The emitted white light was found to be the result of blue, green, and orange emission bands. The blue bands at ∼400 and 459 nm were attributed to sulfur vacancies and surface states, respectively. The green band at ∼511 nm was associated with the singly ionized oxygen vacancy of the ZnO shell layer. The orange emission originated from the 4T 1− 6A 1transition of the Mn 2+ions. Thus, the emissions from the Mn-doped ZnS core and the outer ZnO shell combine together to produce the white light.

Synthesis of thin (5−8 nm) CdS−Mn/ZnS core−shell nanowires (CSNWs) with high aspect ratio (up to ∼150) is reported for the first time. The modified solvothermal synthesis of CSNW involved two steps:  the formation of Mn-doped CdS core followed by the ZnS shell. The CSNW growth process is engineered in such a way that the ZnS shell layer grew radially onto the prematurely grown CdS−Mn core, that is, prior to the formation of its well-faceted surface.

Controlled layering of the deprotonated methanolic solution of the azo-aromatic ligand [L3]– (HL3 = 2-[3-(pyridylamino)phenylazo]pyridine) over the aqueous/methanolic solutions of metal chlorides MCl2 (M = Zn, Hg) afforded nano- and micrometer-sized particles of the metal–organic polymeric complexes of [HgCl(C16H12N5)]∞ (1) and [ZnCl(C16H18N5O3)]∞ (2). Time-dependent growth of the above particles is followed by the SEM and TEM analyses of the samples at different time intervals. The X-ray structure of the mercury polymer reveals that two infinite 1D, zigzag chains composed of [HgCl(L3)]∞ units run along the a axis antiparalelly. The polynuclear Zn compound, in contrast, agglomerates fast to form hemispherical microcrystals with a diamondoid surface morphology, and no suitable X-ray quality crystal of this complex could be isolated. Powder XRD analyses of the samples as well as thermogravimetric analysis (TGA) are used for their characterization. Unusually, these metal–organic polymers of the reference d10 metal ions are green and absorb in the low-energy region of the visible spectrum, 660–675 nm. Semiempirical calculations on a representative complex 1 suggest that the transitions in the complexes involve ligand orbitals. These also show multiple emissions in the blue-green region. The Zn complex, which is microporous, shows reversible adsorption/desorption of N2 and H2 gasses. The mercury polymer, on the other hand, shows poor adsorption ability. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)

ZnO nanotube arrays and self-assembled hierarchical nanostructures are reported here. The ZnO nanostructures were synthesized on Zn foils by a simple solvothermal approach. The hierarchical nanostructures resemble the paint-brush morphology, which consisted of a bunch of self-assembled thin nanowires on a comparatively thick ZnO nanotube wall. Successful creation of surface roughness through controlled etching of the ZnO nanotube walls provided the secondary nucleation centers for the nanowires.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

For Abstract see ChemInform Abstract in Full Text.