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In this paper, a Chou–Yang-type multiplicity distribution comprising a total multiplicity component and a binomial asymmetry component is used to describe charged hadron multiplicity data at [Formula: see text] = 0.9, 7 and 8 TeV from the CMS experiment at CERN. The data was obtained and processed from the CERN Open Data Portal. For the total multiplicity component, it was found that a weighted superposition of a Negative Binomial Distribution (NBD) and a Furry–Yule Distribution (FYD) is able to describe the shoulder-like structure characteristic of Koba–Nielsen–Olesen (KNO) scaling violation well. The mean cluster size produced from collisions was also found to increase with collision energy. A prediction is given for pp collisions at [Formula: see text] = 14 TeV.

Carefully engineered radiofrequency (RF) pulses play a key role in a number of systems such as mobile phone, radar, and magnetic resonance imaging. The design of an RF waveform, however, is often posed as an inverse problem with no general solution. As a result, various design methods each with a specific purpose have been developed based on the intuition of human experts. In this work, we propose an artificial intelligence (AI)-powered RF pulse design framework, DeepRF, which utilizes the self-learning characteristics of deep reinforcement learning to generate a novel RF pulse. The effectiveness of DeepRF is demonstrated using four types of RF pulses that are commonly used. The DeepRF-designed pulses successfully satisfy the design criteria while reporting reduced energy. Analyses demonstrate the pulses utilize new mechanisms of magnetization manipulation, suggesting the potentials of DeepRF in discovering unseen design dimensions beyond human intuition. This work may lay the foundation for an emerging field of AI-driven RF waveform design., Published at Nature Machine Intelligence

The intermittency-type fluctuations as outlined by Bialas and Peschanski in the 1980s is analysed in pppp collisions at \sqrt{s}=s= 0.9, 7 and 8 TeV from the CMS collaboration at CERN. Our preliminary analysis shows that the intermittency exponents in the bin-averaged scaled factorial moments decrease in magnitude with increasing collision energy at the TeV scale, which suggests that the cascading nature of multiparticle production described by the \alphaα-model is weakening. We outline possible areas planned for future studies.

Oscillations in modified combinants (C_jCjs) have been of interest to multiparticle production mechanisms since the 1990s [1]. Recently, there has been a discussion on how these oscillations can be reproduced by compounding a binomial distribution with a negative binomial distribution [2,3]. In this work, we explore a stochastic branching model based on a simple interaction term \lambda\overline{\psi}\phi\psiλψ¯ϕψ for partons and propose a hadronization scheme to arrive at the final multiplicity distribution. We study the effects that compounding our model with a binomial distribution has on C_jCjs and explore its physical implications. We find that there is a significant difference in the oscillations in C_jCjs between high energy pp and p\bar{p}pp‾ scattering that our model can reproduce.

Selective electron beam melting (SEBM) is an established layer additive manufacturing or production process for small-to-medium–sized components of Ti-6Al-4V. Current literature data on SEBM of Ti-6Al-4V are, however, based principally on thin-section (

Achieving a high surface finish is a major challenge for most current metal additive manufacturing processes. We report the first quantitative study of the influence of as-built surface conditions on the tensile properties of Ti-6Al-4V produced by selective electron beam melting (SEBM) in order to better understand the SEBM process. Tensile ductility was doubled along with noticeable improvements in tensile strengths after surface modification of the SEBM-fabricated Ti-6Al-4V by chemical etching. The fracture surfaces of tensile specimens with different surface conditions were characterised and correlated with the tensile properties obtained. The removal of a 650-μm-thick surface layer by chemical etching was shown to be necessary to eliminate the detrimental influence of surface defects on mechanical properties. The experimental results and analyses underline the necessity to modify the surfaces of SEBM-fabricated components for structural applications, particularly for those components which contain complex internal concave and convex surfaces and channels.

Lowering the cost of feedstock powder has been a major issue for wider applications of additive manufacturing (AM) of titanium (Ti) and its alloys. A novel and inexpensive Ti sponge material was selected as a precursor and processed using a CSIRO proprietary powder manipulation technology (PMT). The manipulated powder was characterized in terms of the particle size distribution (PSD), roundness, flowability in the Hall Funnel flowmeter, static angle of repose (AOR), apparent density and tap density. In addition, a universal powder bed (UPB) system was used to characterize the manipulated powder behavior after raking. Two benchmark powders, virgin Arcam Ti-6Al-4V powder and used Arcam Ti-6Al-4V powder, were assessed for a comparison. PMT processing of the Ti powder precursor produced near spherically shaped Ti powder in the size range of 75–106 µm, which performed very similarly to the used Arcam powder in the UPB system. The CSIRO PMT offers a cost-effective manipulation process to produce Ti powder promising for AM applications, while the UPB system allows a quick assessment of the powder spreading behavior in AM processes.

A Chou-Yang Type multiplicity distribution which consists of a stochastic (binomial) component for z = nf - nb and a nonstochastic (Generalized Multiplicity Distribution) component for n = nf + nb, is used to analyze the forward-backward multipicity distributions for hadron hadron collision over a wide range of cms energy. The results are compared with the multiplicity distribution using the Negative Binomial Distribution. Finally, cluster size r = 3.30±0.14 and the correlation parameter b = 0.98 are predicted for 14 TeV.

We study the moments of multiplicty distribution and its relation to the Lee-Yang zeros of the generating function in electron-positron and hadron-hadron high energy collision. Our work shows that GMD moments can reproduce the oscillatory behaviour as shown in the experimental data and predicted by quantum chromodynamics at preasymptotic energy, while it can also be used to distinguish electron-positron (e+e-) multiplicity data from hadron-hadron (pp and [Formula: see text]) multiplicity. Furthermore, there seems to be a link between the development of shoulder structure in the multiplicity distribution and the development of ear structure in the Lee-Yang zeros. We predict that these structures is going to be very obvious at 14 TeV. We argue that the development of these structures indicates an ongoing transition from quark-dominated soft scattering events to gluon-dominated semihard scattering events.

In this work, we study the Lee–Yang solutions of multiplicty distribution (MD) generating function for SPS energies range data. In particular, weighted generalized multiplicity distribution (GMD) function is used to describe the existing shoulder structure in the experimental data. Our study suggest that the existence of the shoulder structure in the KNO plot is accompanied by the forming of an ear structure in the Lee–Yang zeros plot. Prediction for the LHC energy range is also made.

By considering dynamical symmetry between canonically equivalent systems, we investigate the connection between the geometric phase and dynamical invariants, where the Liouville–von-Neumann equation is directly deduced. Furthermore, we show that an arbitrary shift of the Hamiltonian , where fi(t) is a real function and Xi is a generator of dynamical symmetry, leaves the geometric phase invariant.

We discuss a Bell inequality based on correlation function for three qubits. The inequality is violated by any pure entangled state for 3 qubits. The strength of the violation is the same as the result in Ref.13.

We investigate the nature of geometric phases generated by the evolution of the superposition of Dicke states of excitons in N coupled quantum dots. Based on a sequence of laser pulses, arbitrary superposition of the Dicke states of excitons can be generated. By properly choosing the superposition and using the controllable laser pulses, geometric phase with any expected value can be realized. The main advantage of using coupled quantum dots is that one uses a collective behavior, rather than addressing individually qubits, for instance, like with trapped ions configuration, which require a heavy setup in order to perform a gate.

Various enediynes have been successfully cyclized via the alkylpalladium intermediates to the corresponding [m, 5,n] tricyclic compounds.

Double-fractionated palm olein (DfPOo) fractions with iodine values (IV) of 60 and 65 were each blended with low-erucic acid rapeseed (LEAR) oil in various proportions. Clarities of the blends at different temperatures were determined. Maximum levels of DfPOo-IV60 and DfPOo-IV65 in blends that remained clear at 20°C for at least 120 d were 40 and 80%, respectively. At 15°C, the maximum levels were 10 and 40%, and at 10°C, 10 and 20%, respectively. At 5°C, only a blend of 10% DfPOo-IV65 in LEAR remained clear for 120 d. Maximum levels of DfPOo-IV60 and DfPOo-IV65 in blends that passed the cold test were 30% for both palm oleins. Maximum levels of the palm oleins in blends with LEAR were higher than those of blends with soybean oil. Cloud points were lower in palm olein/LEAR blends than those of palm olein/soybean oil blends, probably because LEAR contains less saturated fatty acids than soybean oil.

Isothermal crystallization of plam oil was studied by means of differential scanning calorimetry (DSC) as well as by nuclear magnetic resonance spectrometry to monitor its solid fat content (SFC). The temperature of crystallization (Tc) varied from 0 to 30°C, depending on the method used. The plot of %SFC vs. time at 25°C was sigmoidal in shape. However, at lower temperatures, two consecutive curves were clearly visible. Results from DSC experiments showed the following interesting features. At each Tc, the crystals produced were of different compositions. From 0 to 8°C, the thermogram showed three peaks, with the first two peaks (I and II) sharp, and the third (III) rather broad. At elevated temperatures up to 20°C, peak II disappeared totally while peak III tended to shift toward peak I. Above 20°C, both peaks shifted downward to longer times. Peak I continued to be broadened, and then suddenly disappeared at Tc above 24°C. The melting thermograms of the crystals obtained above and below this cut-off point were distinctly different. Kinetic studies on isothermal crystallization based on the data of SFC measurements showed that the data fit well into the Avrami-Erofeev equation with n=3 over the first 70% of the crystallization.

We have investigated the effects of ultraviolet (UV) irradiation on the characteristics of a -Si:H films and a -Si:H TFTs by employing both a low-pressure mercury lamp and an excimer laser. The intensity of the XeCl excimer laser was varied from 10 to 80 mJ/cm 2 . The electrical properties of a -Si:H films and the characteristics of TFTs that were degraded by various stresses such as visible light soaking (130,000 1x, 1∼8 hrs) and electrical stress (30 V, 8 hrs) for a long period, recovered considerably to their original states after exposure.

Various enediynes have been successfully cyclized via the alkylpalladium intermediates to the corresponding [m, 5,n] tricyclic compounds.

Palladium catalyzed 1,7-eneyne cyclizations proceeded endo- or exo-mode depending on solvent: polar solvent afforded the exo-mode predominantly, non-polar solvent did the endo mode product.

Lyapunov control (open-loop) is often confronted with uncertainties and errors in practical applications. In this paper, we analyze the robustness of Lyapunov control against the uncertainties and errors in quantum control systems. The analysis is carried out through examinations of uncertainties and errors, calculations of the control fidelity under influences of the certainties and errors, as well as discussions on the caused effects. Two examples, a closed control system and an open control system, are presented to illustrate the general formulism., Comment: 4 pages, 5 figures

The aim of the study was to determine the resistance to crystallization of palm olein (POo) with soybean oil (SBO) at different temperatures. POo of iodine value (IV) 65 gave better resistance to crystallization than POo of IV 60 or IV 63. For applications such as salad oil, the use of POo of IV 65 is limited to 30% when blended with SBO. If POo of either IV 60 or IV 63 is chosen, its use in salad oil is limited to 10% only. However, for applications other than salad oil, such as for cooking or frying, 100% POo of any IV could be used. For cold climates, the amount of POo (IV 60 or 63) recommended to get a clear oil is 10–30%. Alternatively, up to 40% POo of IV 65 can be blended with SBO. For temperate climates, the amount of POo (IV 60 or 63) recommended can be up to 60%. With POo of IV 65, the amount recommended is as high as 80–90% for application as a cooking or frying oil.

An RF excitation technique with which one can improve the effective dynamic range of the receiver and reduce the interference between slices for 3D volume-selective multislice MRI is described. The basic idea of the technique is to use phase scrambling in conjunction with slice encoding through the use of RF pulses. The spins in each slice are encoded by RF pulses which have the scrambled as well as slice-encoded phase components along the slice-selection direction. The scrambled, or randomly distributed, phase reduces the peak signal intensity, thereby reducing the dynamic range of the signal. Since the proposed technique utilizes RF slice encoding together with phase scrambling, interslice image interference is greatly reduced and the dynamic range is improved. In addition, the method has several advantages such as a reduction in the power requirement for the RF pulses and the elimination of the necessity for hardware such as nonlinear gradient coils.© 1992 Academic Press,Inc.

Six different brands of commercial shortenings were evaluated for their physicochemical characteristics and baking performance of cakes and biscuits (cookies). Three of the samples were locally made shortenings supplied by three different refineries (coded A, B and C), and the other three samples were imported shortenings obtained from supermarkets in Kuala Lumpur (D, E and F). Analyses and evaluations included slip melting point, solid fat content, fatty acid composition, triglyceride composition, creaming power and baking performance. All of the shortenings had slip melting points above 40°C. Sample A had the highest solid fat content at all temperatures. However, in terms of baking performance in cakes, sample C gave the highest volume, followed closely by samples B and A. Results indicated that the cakes were significantly different (P < 0.05) in terms of grain size and eating quality. Sensory evaluation on biscuits indicated that samples made with shortening D were preferred by a majority of the sensory panel, followed by those made with shortening C. The third, in order of panel preference, was biscuits made with shortening E.

Binary blends of palm mid fraction (PMF) with Borneo tallow (IP) and PMF with sal stearin (SLs) showed eutectic behavior. To produce a cocoa butter extender with steep melting profiles and containing not less than 70% solid fat at 20°C, the maximum amount of PMF1 (IV=49.2) and PMF2 (IV=39.8) that could be added to IP in PMF:IP binary systems were about 10% and 33%; whereas the amount of PMF2 that could be added to SLsl (IV=33.4), SLs2 (IV=31.7) and SLs3 (IV=30.3) in PMF2:SLs binary systems were about 7%, 10% and 38%, respectively. Blends of any PMF with an iodine value of 37 or lower with IP could fulfill the above specifications at any blend ratio.

We propose a new universal quantum computation scheme for trapped ions in thermal motion via the technique of adiabatic passage, which incorporates the advantages of both the adiabatic passage and the model of trapped ions in thermal motion. Our scheme is immune from the decoherence due to spontaneous emission from excited states as the system in our scheme evolves along a dark state. In our scheme the vibrational degrees of freedom are not required to be cooled to their ground states because they are only virtually excited. It is shown that the fidelity of the resultant gate operation is still high even when the magnitude of the effective Rabi frequency moderately deviates from the desired value.

The integrated system of a Very High Temperature Gas-Cooled Reactor (VHTR) and a High Temperature Steam Electrolysis (HTSE) process is one of systems being investigated by the U.S. Department of Energy and Idaho National Laboratory. This system will produce hydrogen by utilizing a highly efficient VHTR with an outlet temperature of 900 °C and supplying necessary energy and electricity to the HTSE process for electrolysis of high temperature steam. This report includes a description of five configurations including an indirect parallel cycle, an indirect serial cycle, a direct serial cycle, a steam combined cycle, and a reheat cycle. HYSYS simulations were performed for each of these configurations coupled to a HTSE process. Final results are presented along with parametric studies and process optimization.

The Department of Energy and the Idaho National Laboratory are developing a Next Generation Nuclear Plant (NGNP) to serve as a demonstration of state-of-the-art nuclear technology. The purpose of the demonstration is two fold 1) efficient low cost energy generation and 2) hydrogen production. Although a next generation plant could be developed as a single-purpose facility, early designs are expected to be dual-purpose. While hydrogen production and advanced energy cycles are still in its early stages of development, research towards coupling a high temperature reactor, electrical generation and hydrogen production is under way. Many aspects of the NGNP must be researched and developed in order to make recommendations on the final design of the plant. Parameters such as working conditions, cycle components, working fluids, and power conversion unit configurations must be understood. Three configurations of the power conversion unit were demonstrated in this study. A three-shaft design with 3 turbines and 4 compressors, a combined cycle with a Brayton top cycle and a Rankine bottoming cycle, and a reheated cycle with 3 stages of reheat were investigated. An intermediate heat transport loop for transporting process heat to a High Temperature Steam Electrolysis (HTSE) hydrogen production plant was used. Helium, CO2, and an 80% nitrogen, 20% helium mixture (by weight) were studied to determine the best working fluid in terms cycle efficiency and development cost. In each of these configurations the relative component size were estimated for the different working fluids. The relative size of the turbomachinery was measured by comparing the power input/output of the component. For heat exchangers the volume was computed and compared. Parametric studies away from the baseline values of the three-shaft and combined cycles were performed to determine the effect of varying conditions in the cycle. This gives some insight into the sensitivity of these cycles to various operating conditions as well as trade offs between efficiency and capital cost. Prametric studies were carried out on reactor outlet temperature, mass flow, pressure, and turbine cooling. Recommendations on the optimal working fluid for each configuration were made. A steady state model comparison was made with a Closed Brayton Cycle (CBC) power conversion system developed at Sandia National Laboratory (SNL). A preliminary model of the CBC was developed in HYSYS for comparison. Temperature and pressure ratio curves for the Capstone turbine and compressor developed at SNL were implemented into the HYSYS model. A comparison between the HYSYS model and SNL loop demonstrated power output predicted by HYSYS was much larger than that in the experiment. This was due to a lack of a model for the electrical alternator which was used to measure the power from the SNL loop. Further comparisons of the HYSYS model and the CBC data are recommended. Engineering analyses were performed for several configurations of the intermediate heat transport loop that transfers heat from the nuclear reactor to the hydrogen production plant. The analyses evaluated parallel and concentric piping arrangements and two different working fluids, including helium and a liquid salt. The thermal-hydraulic analyses determined the size and insulation requirements for the hot and cold leg pipes in the different configurations. Economic analyses were performed to estimate the cost of the va

The relative lack of successful pancreatic differentiation of human embryonic stem cells (hESCs) may suggest that directed differentiation of hESCs into definitive endoderm and subsequent commitment towards a pancreatic fate are not readily achieved. The aim of this study was to investigate whether sequential exposure of hESCs to epigenetic signals that mimic in vivo pancreatic development can efficiently generate pancreatic endodermal cells, and whether these cells can be further matured and reverse hyperglycaemia upon transplantation.The hESCs were sequentially treated with serum, activin and retinoic acid (RA) during embryoid body formation. The patterns of gene expression and protein production associated with embryonic germ layers and pancreatic endoderm were analysed by RT-PCR and immunostaining. The developmental competence and function of hESC-derived PDX1-positive cells were evaluated after in vivo transplantation.Sequential treatment with serum, activin and RA highly upregulated the expression of the genes encoding forkhead box protein A2 (FOXA2), SRY-box containing gene 17 (SOX17), pancreatic and duodenal homeobox 1 (PDX1) and homeobox HB9 (HLXB9). The population of pancreatic endodermal cells that produced PDX1 was significantly increased at the expense of ectodermal differentiation, and a subset of the PDX1-positive cells also produced FOXA2, caudal-type homeobox transcription factor 2 (CDX2), and nestin (NES). After transplantation, the PDX1-positive cells further differentiated into mature cell types producing insulin and glucagon, resulting in amelioration of hyperglycaemia and weight loss in streptozotocin-treated diabetic mice.Our strategy allows the progressive differentiation of hESCs into pancreatic endoderm capable of generating mature pancreatic cell types that function in vivo. These findings may establish the basis of further investigations for the purification of transplantable islet progenitors derived from hESCs.