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To investigate the effect of intermittent aeration on oxygen dynamics, organic matter degradation and main gas emissions, a lab-scale pig manure composting experiment was conducted with intermittent aeration (I_A, 30-min on and 30-min off) and continuous aeration (C_A). Although aeration volume and oxygen supply of I_A was only half of C_A, I_A could obviously enhance the oxygen utilization efficiency by 96.67 % and reduce energy dissipation for aeration by 50.87 %. Based on the comprehensive analysis of total organic matter, total carbon, total nitrogen, cellulose, hemicellulose and lignin contents, there was no significant difference in organic matter degradation between I_A and C_A (p 0.05). Moreover, a reduction of 21.71 %, 38.93 %, 44.40 % and 62.19 % of CH

InGaN nanowires (NWs) are grown on pyramid textured Si substrates by stationary plasma-assisted molecular beam epitaxy (PA-MBE). The incidence angles of the highly directional source beams vary for different pyramid facets, inducing a distinct inter-facet modulation of the In content of the InGaN NWs, which is verified by spatial element distribution analysis. The resulting multi-wavelength emission is confirmed by photoluminescence (PL) and cathodoluminescence (CL). Pure GaN phase formation dominates on certain facets, which is attributed to extreme local growth conditions, such as low active N flux. On the same facets, InGaN NWs exhibit a morphology change close to the pyramid ridge, indicating inter-facet atom migration. This cross-talk effect due to inter-facet atom migration is verified by a decrease of the inter-facet In content modulation amplitude with shrinking pyramid size. A detailed analysis of the In content variation across individual pyramid facets and element distribution line profiles reveals that the cross-talk effect originates mainly from the inter-facet atom migration over the convex pyramid ridge facet boundaries rather than the concave base line facet boundaries. This is understood by first-principles calculations showing that the pyramid baseline facet boundary acts as an energy barrier for atom migration, which is much higher than that of the ridge facet boundary. The influence of the growth temperature on the inter-facet In content modulation is also presented. This work gives deep insight into the composition modulation for the realization of multi-color light-emitting devices based on the monolithic growth of InGaN NWs on pyramid textured Si substrates.

We introduce a novel concept for the design of functional surfaces of materials: Spatial surface charge engineering. We exploit the concept for an all-solid-state, epitaxial InN/InGaN-on-Si reference electrode to replace the inconvenient liquid-filled reference electrodes, such as Ag/AgCl. Reference electrodes are universal components of electrochemical sensors, ubiquitous in electrochemistry to set a constant potential. For subtle interrelation of structure design, surface morphology and the unique surface charge properties of InGaN, the reference electrode has less than 10 mV/decade sensitivity over a wide concentration range, evaluated for KCl aqueous solutions and less than 2 mV/hour long-time drift over 12 hours. Key is a nanoscale charge balanced surface for the right InGaN composition, InN amount and InGaN surface morphology, depending on growth conditions and layer thickness, which is underpinned by the surface potential measured by Kelvin probe force microscopy. When paired with the InN/InGaN quantum dot sensing electrode with super-Nernstian sensitivity, where only structure design and surface morphology are changed, this completes an all-InGaN-based electrochemical sensor with unprecedented performance.

In this paper, we analyze the macroscopic entanglement generation between two movable mirrors in an optomechanical system beyond the Markov approximation. We derive a non-Markovian master equation for the optomechanical system and analyze the entanglement generation based on the numerical simulation. It is found that the maximum entanglement can be achieved by utilizing both the optomechanical coupling and the non-Markovian properties of the bath. In particular, we show the contribution from the system-bath coupling has a positive impact only if the bath is non-Markovian. Besides, the symmetric properties of the optomechanical system as well as the initial state are crucial to the entanglement generation. The results presented in the paper illustrate that the impact of the non-Markovian bath is an important factor in the entanglement generation in the optomechanical system.

Summary Aerobic composting is a bacteria‐driven process to degrade and recycle wastes. This study quantified the kinetics of bacterial growth and decay during pig manure–wheat straw composting, which may provide insights into microbial reaction mechanisms and composting operations. First, a propidium monoazide–quantitative polymerase chain reaction (PMA–qPCR) method was developed to quantify the viable bacteria concentration of composting samples. The optimal PMA concentration and light exposure time were 100 μM and 8 min respectively. Subsequently, the concentrations of total and decayed bacteria were quantified. Viable and decayed bacteria coexisted during the entire composting period (experiments A and B), and the proportion of viable bacteria finally fell to only 35.1%. At the beginning, bacteria grew logarithmically and decayed rapidly. Later, the bacterial growth in experiment A remained stable, while that of experiment B was stable at first and then decomposed. The duration of the stable stage was positively related to the soluble sugar content of composting materials. The logarithmic growth and rapid decay of bacteria followed Monod equations with a specific growth (0.0317 ± 0.0033 h−1) and decay rate (0.0019 ± 0.0000 h−1). The findings better identified the bacterial growth stages and might enable better prediction of composting temperatures and the degree of maturation.

In this paper, we propose a scheme to protect quantum coherence by adding another noise. We consider an example of a Jaynes–Cummings model coupled to an external non-Markovian bosonic bath. We solve this model by using the dressed state method in the presence of a stochastic coupling and obtain the density matrix by numerically averaging many stochastic trajectories. We show that the noisy atom-cavity coupling can effectively suppress both the relaxation and dephasing effects caused by the leakage of the cavity. Besides, we further illustrate the impacts of the standard deviation of the noisy coupling and the non-Markovian memory effect on the coherence protection. Then, the mechanism of the protection is analyzed. It is our hope that our research may open a new path to consider the role of noise in quantum coherence preservation.

This study explored the effects of different particle sizes of rice straw biochar (RSB) on the methane emissions of pig manure/wheat straw aerobic composting experiments to provide a theoretical suggestion for biochar application. The experiments were conducted with a control group, powder (1 mm) group, and granular (4 mm-1 cm) group. Methane emissions increased by 56.84% in the powder group but decreased by 22.15% in the granular group during the aerobic composting. Methane was generated by methanogens and methanotrophs in the specific anaerobic micro-environment characterized by X-ray micro-computed tomography (micro-CT). The porosity of initial composting samples increased by 4.02% in the granular group but decreased by 3.88% in the powder group. RSB additives typically reduced the mcrA/pmoA ratio and increased the diversity of Bacteria and Archaea. Conclusively, granular biochar benefits to aerobic composting to alleviate the CH

A 28.5-38.5GHz wide tuning range VCO (Voltage Controlled Oscillator) for 5G Millimeter Wave Communication is presented. Benefiting from the LC cross-coupled oscillation structure, a careful tank design was carried out to achieve a minimum phase noise. The oscillation frequency is tuned both by a capacitor array and a variable capacitor. Based on the layout drawing and the parasitic parameter extraction simulation, the post simulation results show that the VCO frequency range from 28.5GHz to 38.5GHz. Implemented in a 55nm CMOS technology, the 29.85%-tuning-range VCO shows a phase noise as low as -107.2dBc/Hz at 1MHz offset from a 33. 5GHz carrier while consuming 32.07mA on average from a 1.8V power supply.

We demonstrate multi-wavelength light emission from InGaN nanowires (NWs) monolithically grown on pyramid-textured Si(100) substrates by plasma-assisted molecular beam epitaxy (MBE) under stationary conditions. Taking advantage of the highly unidirectional source material beam fluxes, the In content of the NWs is tuned on the different pyramid facets due to varied incidence angle. This is confirmed by distinct NW morphologies observed by scanning electron microscopy (SEM) and by energy-dispersive X-ray (EDX) element mapping. Photoluminescence and cathodoluminescence (CL) reveal multiple lines originating from InGaN NWs on the different pyramid facets. The anomalous temperature dependence of the emission wavelength results from carrier redistribution between localized or confined states, spontaneously formed within the NWs due to composition fluctuations, verified by high-resolution EDX elemental analysis. First-principles calculations show that the pyramid facet edges act as a barrier for atom migration and enhance atom incorporation. This leads to uniform composition within the facets for not too high a growth temperature, consistent with the SEM, EDX and CL results. At elevated temperature, InGaN decomposition and In desorption are enhanced on facets with low growth rate, accompanied by Ga inter-facet migration, leading to non-uniform composition over the Ga migration length which is deduced to be around 580 nm. Our study presents a method for the fabrication of multi-wavelength light sources by highly unidirectional MBE on textured Si substrates towards color temperature-tunable solid-state lighting and RGB light-emitting diode displays.

We directly measure the electric dipole of InN quantum dots (QDs) grown on In-rich InGaN layers by Kelvin probe force microscopy. This significantly advances the understanding of the superior catalytic performance of InN/InGaN QDs in ion- and biosensing and in photoelectrochemical hydrogen generation by water splitting and the understanding of the important third-generation InGaN semiconductor surface in general. The positive surface photovoltage (SPV) gives an outward QD dipole with dipole potential of the order of 150 mV, in agreement with previous calculations. After HCl-etching, to complement the determination of the electric dipole, a giant negative SPV of −2.4 V, significantly larger than the InGaN bandgap energy, is discovered. This giant SPV is assigned to a large inward electric dipole, associated with the appearance of holes, matching the original QD lateral size and density. Such surprising result points towards unique photovoltaic effects and photosensitivity.

This paper introduces a design of a high-speed programmable multi-modulus divider (MMD) based on 65nm CMOS process. The design adopts the cascade structure of 7 level 2/3 frequency dividers, and expands the frequency division range by adjusting the number of cascade stages, so as to achieve a continuous frequency division ratio of 16 to 255. Among them, the first level 2/3 frequency divider adopts the D flip-flop design of CML (current mode logic) structure, the second level 2/3 frequency divider adopts the D flip-flop design of E-TSPC (extended true-single-phase-clock) structure. The whole circuit realizes the working frequency range of 13∼18GHz high frequency and large bandwidth. This design has completed layout drawing and parasitic parameter extraction simulation. The simulation results show that the operating frequency range of the circuit can reach 13∼18GHz. When the input signal is 18GHz and the frequency division ratio is 255, the phase noise is about -135dBc/Hz@1kHz. It has the advantages of high frequency, large bandwidth, and low phase noise.

Assembling colloidal particle under oscillatory electric field (OEF) has become an emerging bottom-up technique to synthesize advanced materials and fabricate micro/nano devices. Surfactants have been often used in colloid dispersions for improving their stability. However, the precise roles of surfactants in particle assembly processes under OEF are unknown. Here, we systematically study the effects of ionic surfactants on the colloidal particle assembling process subject to a fixed OEF, by using an anionic surfactant (sodium dodecyl sulfate, SDS) and a cationic surfactant (cetyltrimethylammonium bromide, CTAB). In the concentration range below the critical micelle concentration (CMC), the particles tend to form three different aggregate structures, including randomly close-packed (RCP), hexagonally closed-packed (HCP) crystal, and randomly nonclose-packed (RNCP) structures. In the concentration range at CMC and above, the particles cannot assemble into any aggregate structures under the given OEF. With increasing the surfactant concentration, the average interparticle separation distance within the aggregate can be regulated in a wide range. We qualitatively interpret the observed variation of particle assembling behaviors in different surfactant solutions based on the particle/particle interaction energy, implying that the repulsive EDL interaction is significantly enhanced with increasing the ionic surfactant concentration and hinders the particles approaching close with high energy barrier. These results suggest that the particle aggregate structures and interparticle separation distance of the 2D colloidal assembly can be manipulated by controlling the ionic surfactant concentration according to the requirements of practical applications.

In the age of information network, blockchain technology has become a key focus. With the integration of new technologies, blockchain covers many fields such as finance, social welfare, agriculture, smart cities, and education. At the same time, education has undergone fundamental changes along with the continuous advancement of technology, and under the impetus of blockchain and other technologies, “technology better empowers education” is an important goal of education informatization workers. Therefore, this article will explore its application scenarios in the field of “blockchain + education” based on blockchain and IPFS-related technologies and elaborate on how IPFS technology can improve the efficiency of educational resource sharing, optimize the process of sharing and dissemination of educational resources, promote the improvement of the quality of science education and build the application prospects of science education resource sharing.

In recent years, computer vision technology in the field of science and technology has been stubbornly high, making a lot of scientific and technical personnel involved in the research gate technology. Depth learning, artificial intelligence in recent years, often around our ears, vision technology is occupying a place in the field of artificial intelligence. This paper mainly studies the recognition and localization of robots based on vision. The mobile robot is detected by the background difference method, and the background model is established by the Gaussian background modeling. Recognizing the color and number tags on the robot for matching the robot’s features. Real-time positioning of the robot under the premise of the same background.

We study Ⅲ-nitride nanowire (NW) anti-reflection structures employed as photoelectrocatalyst for solar water splitting. We found that 1D vertical InGaN NW arrays tilted by 73° exhibit maximized photocurrent. Therefore, we grow 3D InGaN NW arrays on the facets of oblique pyramid-textured Si (311) (OPSi/InGaN) by plasma-assisted molecular beam epitaxy, exhibiting facets tilted by 73°. In addition, using finite difference time domain simulations we find the crucial impact of the asymmetry of the oblique pyramid InGaN NW arrays on the light trapping. Compared with InGaN NWs grown on a planar Si substrate (Si/InGaN), the OPSi/InGaN photoanode exhibits ~500% enhancement of the photocurrent due to various light trapping effects attributed to: 1D vertical NW arrays, their tilt, 3D arrangement and asymmetry. Decorated with NiOOH co-catalyst, the OPSi/InGaN photoanode exhibits photocurrent densities in the mA cm−2 range. The present research provides a rational design for the fabrication of nanostructured photoelectrocatalyst with enhanced light absorption.

To investigate the emission mechanism of ammonia (NH3) and nitrous oxide (N2O) during aerobic composting and the influence of powder bamboo biochar (PBB) on this process, this paper conducted a systematic study on the nitrogen-transforming functional microbial community, including functional genes, microbial structure and metabolism pathways. PBB reduced N2O and NH3 emissions by 1.25%-8.72% and 10.4%-11.8%, respectively. The quantitative PCR results indicated that the reduced N2O emission by PBB were mainly related to denitrifying genes (nirS, nirK, nosZ, and narG). The metagenome results demonstrated that Nitrosococcus was the main genus that could oxidize ammonia to nitrite decreased by PBB. The PBB significantly affected the nitrogen metabolism pathway, reduced the activity of glutamate dehydrogenase to inhibit the formation of NH4+ to reduce NH3 emission. The higher N2O emission in the control group was also related to the higher relative contents of hydroxylamine reductase and nitrite reductase.

We demonstrate the feasibility of p-type Cu2O as a hole injection/collection layer on low-bandgap In-rich InGaN nanowires (NWs). This overcomes the difficulty of p-type doping of In-rich InGaN and the use of wide-bandgap low-In-content p-type InGaN layers. The n-type InGaN NWs with 45% In content are grown by plasma-assisted molecular beam epitaxy and the Cu2O layers on top are fabricated by electrodeposition at low temperature. The Cu2O/InGaN heterostructure is characterized by x-ray diffraction, scanning electron microscopy, energy dispersive x-ray spectroscopy, transmission electron microscopy, Raman spectroscopy, photoluminescence spectroscopy, and current–voltage measurements. For sufficient Cu2O deposition amount to form a fully coalesced, compact layer and optimized Cu2O deposition temperature of 35 °C, the current–voltage curve shows a clear rectifying behavior with a rectification ratio close to 5 at ±3 V and turn-on voltage of 1.45 V. This reveals the successful hole injection from p-type Cu2O into n-type In-rich InGaN, but the obviously still high interface state density requires further improvement.

We demonstrate an all-solid-state potentiometric sensor constructed from solid-state InN/InGaN sensing- and reference electrodes with the epitaxial InN/InGaN layers directly grown on Si substrates. The sensor, evaluated in KCl aqueous solution, exhibits super-Nernstian sensitivity of −78 mV/decade with good linearity for concentrations of 0.01–1 M, which is the physiologically relevant range. Good stability and re-usability are demonstrated by a long-time drift below 0.2 mV h−1 and standard deviation of 8 mV for repeated measurements over 10 d. These properties fulfil the requirements for compact, robust and highly sensitive all-solid-state sensors and sensor arrays.

Greenhouse gas and ammonia emissions during composting with different biochar types and particle sizes were investigated. Compared with powder-biochar, granular-biochar improved pore connectivity and was benefit to methanotrophs activities, like Methylococcaceae, reducing CH4 emissions. At the same particle size, bamboo biochar (BB) had a higher pore volume and more aerobic microenvironment within the compost than rice straw biochar (RSB), reducing GHG emissions. Bamboo biochar had high aromatic compound and NO3- concentrations and therefore surface π-π electron donor/acceptor interactions, causing low N2O emissions and inhibiting denitrifying bacteria (e.g., Bacteroidales). More CO and CO bonds in rice straw biochar than bamboo biochar caused lower NH3 emissions using rice straw than bamboo biochar. Powdered biochar had more exposed reactive functional groups and decreased NH3 production better than granular biochar. Powdered bamboo biochar controls gaseous emissions better than other biochars during aerobic pig manure/wheat straw composting.

In this study, 100 mg/kg of amoxicillin (AMX) was added to pig manure during aerobic composting using a laboratory-scale reactor system, for better understanding the degradation of AMX and its potential risks. Qualitative and quantitative analysis of AMX and its main degradation products (DPs) were then conducted using solid phase extraction combined with high performance liquid chromatography-tandem mass spectrometry. Additionally, hydrolysis testing was performed to monitor DPs produced from AMX degradation under various controlled conditions. The results showed that AMX was unstable in compost and rapidly degraded into AMX penicilloic acid, AMX penilloic acid and AMX diketopiperazine, which all eventually degraded, leaving a structurally simple and stable end product, 3-(4-hydroxyphenyl) pyrazin-2-ol, which appeared to be nonallergenic and less toxic than DPs generated earlier in the composting process. Besides, AMX was more unstable and more apt to generate multiple DPs in alkaline conditions than in acidic or neutral conditions or in ultrapure water, while pH exerted a larger effect on AMX degradation than did divalent metal ions (Cu2+ and Zn2+). This study provides technical and methodological support to better achieve AMX residual treatment and to evaluate the safety of AMX DPs produced in huge quantities in compost in China.

This study investigated the effects of biochar powder on oxygen supply efficiency and global warming potential (GWP) in the large-scale aerobic composting pattern which includes cyclical forced-turning with aeration at the bottom of composting tanks in China. A 55-day large-scale aerobic composting experiment was conducted in two different groups without and with 10% biochar powder addition (by weight). The results show that biochar powder improves the holding ability of oxygen, and the duration time (O2 >5%) is around 80%. The composting process with above pattern significantly reduce CH4 and N2O emissions compared to the static or turning-only styles. Considering the average GWP of the BC group was 19.82% lower than that of the CK group, it suggests that rational addition of biochar powder has the potential to reduce the energy consumption of turning, improve effectiveness of the oxygen supply, and reduce comprehensive greenhouse effects.

The binding mode between the pentapeptide (DHTKE) from egg white hydrolysates and calcium ions was elucidated upon its structural and thermodynamics characteristics. The present study demonstrated that the DHTKE peptide could spontaneously bind calcium with a 1:1 stoichiometry, and that the calcium-binding site corresponded to the carboxyl oxygen, amino nitrogen, and imidazole nitrogen atoms of the DHTKE peptide. Moreover, the effect of the DHTKE-calcium complex on improving the calcium absorption was investigated in vitro using Caco-2 cells. Results showed that the DHTKE-calcium complex could facilitate the calcium influx into the cytosol and further improve calcium absorption across Caco-2 cell monolayers by more than 7 times when compared to calcium-free control. This study facilitates the understanding about the binding mechanism between peptides and calcium ions as well as suggests a potential application of egg white peptides as nutraceuticals to improve calcium absorption.