Mixed-culture microbial protein from waste sulfite pulping liquor II: Its production on pilot-plant scale and use in animal feed

This paper describes a pilot plant system set up to produce a mixed-culture biomass having a very high content of protein (43%), for use in animal feed. Waste liquor from sulfite pulping was used as substrate. Conversion of carbohydrates in the said liquor to biomass was carried out in a 1200-liter, nonaseptic, aerated, continuous flow tank fermentor. Fermentation conducted at pH = 6.5 gave rise to better settling of microorganisms than at the other pH's studied. The air input was a very important factor affecting fermentor productivity. Under the operating conditions used, the results for carbohydrate conversion, BOD₅ reduction, biomass yield coefficient, and productivity were respectively, 90%, 85%, 0.53 kg/kg, and 3.67 kg/(m³d). With respect to the whole production system, operating and/or control problems were identified and useful technical data were collected in view of an eventual industrial implantation. The final product consisted of about the same varieties of microorganisms (yeasts, bacteria and microfungi) obtained in our previous work, Its nutritive qualities were not affected by the scale-up of fermentor, i.e., from the previous 400 liters to the present 1200 liters. Animal feeding experiments were conducted using 240 chickens fed 4 diets. At least 50% of the soybean protein in commercial diet could be replaced with the biomass protein, without creating a significant effect on growth performance, on the health status of animals examined ante-mortem and post-mortem, and on the organoleptic quality of chicken meat.     

Note: A scanning thermal probe microscope that operates in liquids

We have developed a scanning thermal probe microscope that operates in liquid environments. The thermal sensor is a fluorescent particle glued at the end of a sharp tungsten tip. Since light emission is a strongly thermally sensitive effect, the measurement of the particle fluorescence variations allows the determination of the temperature. No electrical wiring of the probe is needed. As a demonstrative example, we have measured the temperature map of a Joule-heated microheater immersed in a water∕glycerol solution. Both topographical and thermal images are obtained with a good sensitivity.     

High Performance p‐ and n‐Type Light‐Emitting Field‐Effect Transistors Employing Thermally Activated Delayed Fluorescence

Light‐emitting field‐effect transistors (LEFETs) are an emerging type of devices that combine light‐emitting properties with logical switching function. One of the factors limiting their efficiency stems from the spin statistics of electrically generated excitons. Only 25% of them, short lived singlet states, are capable of light emission, with the other 75% being long lived triplet states that are wasted as heat due to spin‐forbidden processes. Traditionally, the way to overcome this limitation is to use phosphorescent materials as additional emission channel harnessing the triplet excitons. Here, an alternative strategy for triplet usage in LEFETs in the form of thermally activated delayed fluorescence (TADF) is presented. Devices employing a TADF capable material, 4CzIPN (2,4,5,6‐tetra[9H‐carbazol‐9‐yl]isophthalonitrile), in both n‐type and p‐type configurations are shown. They manifest excellent electrical characteristics, consistent brightness in the range of 100–1,000 cd m^‐2 and external quantum efficiency (EQE) of up to 0.1%, which is comparable to the equivalent organic light‐emitting diode (OLED) based on the same materials. Simulation identifies the poor light out‐coupling as the main reason for lower than expected EQEs. Transmission measurements show it can be partially alleviated using a more transparent top contact, however more structural optimization is needed to tap the full potential of the device.     

Novel Integration of Metal–Insulator–Metal (MIM) Capacitors Comprising Perovskite-type Dielectric and Cu Bottom Electrode on Low-Temperature Packaging Substrates

In this letter, a novel integration scheme, for metal-insulator-metal capacitors comprising perovskite-type dielectrics and Cu-based bottom electrodes, has been demonstrated on low-temperature FR4 packaging substrates. Cu oxidation during dielectric deposition and postannealing is completely avoided by a dielectric-first process flow with Ti as oxygen-getter. By using evaporated barium strontium titanate as capacitor dielectric, a maximum capacitance density (~1250 nF/cm² at 100 kHz) and moderate leakage current (< 4 times 10^-5 A/cm² at 2 V) have been achieved with rapid thermal annealing at 700degC. Higher temperature leads to dielectric degradation. Combined with advanced deposition techniques, this integration scheme enables realization of high-performance embedded capacitors that can be integrated with printed circuit board technology.     

A chaotic map‐based anonymous multi‐server authenticated key agreement protocol using smart card

Authenticated key agreement protocols play an important role for network‐connected servers to authenticate remote users in Internet environment. In recent years, several authenticated key agreement protocols for single‐server environment have been developed based on chaotic maps. In modern societies, people usually have to access multiple websites or enterprise servers to accomplish their daily personal matters or duties on work; therefore, how to increase user's convenience by offering multi‐server authentication protocol becomes a practical research topic. In this study, a novel chaotic map‐based anonymous multi‐server authenticated key agreement protocol using smart card is proposed. In this protocol, a legal user can access multiple servers using only a single secret key obtained from a trusted third party, known as the registration center. Security analysis shows this protocol is secure against well‐known attacks. In addition, protocol efficiency analysis is conducted by comparing the proposed protocol with two recently proposed schemes in terms of computational cost during one authentication session. We have shown that the proposed protocol is twice faster than the one proposed by Khan and He while preserving the same security properties as their protocol has. Copyright © 2014 John Wiley & Sons, Ltd.     

Direct Heating Amino Acids with Silica: A Universal Solvent‐Free Assembly Approach to Highly Nitrogen‐Doped Mesoporous Carbon Materials

A general solvent‐free assembly approach via directly heating amino acid and mesoporous silica mixtures is developed for the synthesis of a family of highly nitrogen‐doped mesoporous carbons. Amino acids have been used as the sole precursors for templating synthesis of a series of ordered mesoporous carbons. During heating, amino acids are melted and strongly interact with silica, leading to effective loading and improved carbon yields (up to ≈25 wt%), thus to successful structure replication and nitrogen‐doping. Unique solvent‐free structure assembly mechanisms are proposed and elucidated semi‐quantitatively by using two affinity scales. Significantly high nitrogen‐doping levels are achieved, up to 9.4 (16.0) wt% via carbonization at 900 (700) °C. The diverse types of amino acids, their variable interactions with silica and different pyrolytic behaviors lead to nitrogen‐doped mesoporous carbons with tunable surface areas (700–1400 m² g^?1), pore volumes (0.9–2.5 cm³ g^?1), pore sizes (4.3–10 nm), and particle sizes from a single template. As demonstrations, the typical nitrogen‐doped carbons show good performance in CO₂ capture with high CO₂/N₂ selectivities up to ≈48. Moreover, they show attractive performance for oxygen reduction reaction, with an onset and a half‐wave potential of ≈?0.06 and ?0.14 V (vs Ag/AgCl).     

Volume scattering of distributed microbubbles and its influence on blood flow estimation

In recent years, microbubble contrast agents have become a potential adjunct in Doppler ultrasound diagnosis. In this paper, we show that volume scattering makes the effective band in Doppler spectrum shift downward after injection of microbubbles. Because the insonified volume comprises a collection of distributed microbubbles, the statistical properties such as the autocorrelation function and ensemble average power spectrum of the echoes from a collection of distributed microbubbles were derived first. It can be observed that, beyond a critical frequency, the theoretical volume backscattering cross section derived from the ensemble average power spectrum of microbubbles decreases with frequency. On the contrary, the volume backscattering cross section of red cells increases with frequency. Using two-dimensional (2-D) Fourier transform, the variation in Doppler spectrum caused by different volume backscattering cross section can be demonstrated, and the consequential downward shifts of the estimated Doppler parameters (e.g., the mean and maximum Doppler shifts, and the variance of Doppler power spectrum) after microbubble injection are shown. In addition, it can be observed that the variation gets larger as the transmitted bandwidth increases. And, the variations in Doppler parameters estimated with experimental data are presented to verify the theoretical deviations.     

Preliminary evaluation of the seismic response of the ELSY LFR

The main goal of the present study is the preliminary evaluation of the seismic demand of a LFR with reference to European Lead System project (ELSY) considered one of the most promising innovative Generation IV reactor. The safety aspects of the ELSY reactor in the event of a Safe Shutdown Earthquake, taking into account also the effects of the possible fluid–structure interaction, have been analyzed.To the purpose to determine the seismic demand, in according with the international rules, a non-linear dynamic analysis method was used with rather refined 3-D model of LFR for the foreseen structural analyses and simulations of the plant and of the reactor internals behaviour. In this report numerical results are presented and discussed highlighting the relevance of the fluid–structure interaction in terms of structural integrity as well as the isolation technique effectiveness, which is expected to increase the safety margin of the reactor structures during a seismic event, if the isolators frequency is far from that of the reactor.The present work has been performed within the 6th European Framework Project.     

Wafer bonding technology and its applications in optoelectronicdevices and materials

The direct wafer bonding process has found broad applications in many critical areas including both commercial and state-of-the-art photonic devices and more recently, formation of semiconductor compliant substrates. Using the wafer bonding technology, we have demonstrated 1.3-μm vertical-cavity surface-emitting lasers (VCSELs) with a 1-mA continuous-wave (CW) threshold current and 0.83-mA pulsed threshold current. Superior device performance has also been achieved with photodetectors and micromachined tunable devices. Applying the wafer bonding process in a novel way, we have fabricated compliant universal substrates on which largely mismatched (e.g., 15% mismatch) heteroepitaxial layers can be grown defect free