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Efficient heat management and control in optical devices, facilitated by advanced thermo‐optic materials, are critical for many applications such as photovoltaics, thermal emitters, mode‐locked lasers, and optical switches. Here, a range of thermo‐optic properties of 2D graphene oxide (GO) films are investigated by precisely integrating them onto microring resonators (MRRs) with control over the film thicknesses and lengths. The refractive index, extinction coefficient, thermo‐optic coefficient, and thermal conductivity for the GO films with different layer numbers and degrees of reduction, as well as reversible reduction and enhanced optical bistability induced by the photo‐thermal effects, are comprehensively characterized. Experimental results show that the thermo‐optic properties of 2D GO films vary widely with the degree of reduction. In addition, significant anisotropy is observed for the thermo‐optic response, enabling efficient polarization‐sensitive devices. The versatile thermo‐optic response of 2D GO substantially expands the scope of functionalities and devices that can be engineered, making it promising for a diverse range of thermo‐optic applications. [ABSTRACT FROM AUTHOR]

As a rapidly expanding family of 2D materials, MXenes have recently gained considerable attention. Herein, by developing a coating method that enables transfer‐free and layer‐by‐layer film coating, the nonlinear optical absorption (NOA) of Ti3C2Tx MXene films is investigated. Using the Z‐scan technique, the NOA of the MXene films is characterized at ≈800 nm. The results show that there is a strong and layer‐dependent NOA behavior, transitioning from reverse saturable absorption (RSA) to saturable absorption (SA) as the layer number increases from 5 to 30. Notably, the nonlinear absorption coefficient β changes significantly from ≈7.13 × 102 cm GW−1 to ≈−2.69 × 102 cm GW−1 within this range. The power‐dependent NOA of the MXene films is also characterized, and a decreasing trend in β is observed for increasing laser intensity. Finally, the NOA of 2D MXene films at ≈1550 nm is characterized by integrating them onto silicon nitride waveguides, where an SA behavior is observed for the films including 5 and 10 layers of MXene, in contrast to the RSA observed at ≈800 nm. These results reveal intriguing nonlinear optical properties of 2D MXene films, highlighting their versatility and potential for implementing high‐performance nonlinear photonic devices. [ABSTRACT FROM AUTHOR]

Summary: Protein oxidation is widely present in food systems and is susceptible to internal factors involving lipids and enzymes as well as external factors such as temperature and oxygen promoters. Protein oxidation leads to modification of the peptide skeletons and amino acid side chains, which in turn alters the structural characteristics of proteins, including protein cleavage, aggregation and derivative formation, and severely affects their physicochemical properties and bioavailability, thereby reducing the edible and storage qualities of foods. This review summarises the main factors that cause and regulate oxidation of plant protein, the effects of protein oxidation on food quality and strategies to ameliorate protein over‐oxidation, aiming to provide meaningful information for the development of high‐quality plant protein products. [ABSTRACT FROM AUTHOR]

Summary: Soybean meal is an important and inexpensive source of protein in food and animal feed, and contains anti‐nutritional factors such as trypsin inhibitors, antigenic proteins, oligosaccharides, phytic acids and lectins, which limit its application. Microbial fermentation has the capability to improve the nutritional value and biological activities of soybean meal by changing its natural composition. Fermentation results in the degradation of anti‐nutritional factors in soybean meal, an increased amount of small molecular protein peptides and improved content of isoflavone aglycone. However, the nutritional composition and biological activities of the resulting fermented products differ due to the different microbial species and conditions used for fermentation. Compared to soybean meal, fermented soybean meal has several beneficial effects such as digestibility, antioxidant and hypoallergenicity. The objective of this review is to discuss the fermentation processes of soybean meal, as well as outlines some biological activities associated with it. Furthermore, the current application of fermented soybean meal is also summarised. [ABSTRACT FROM AUTHOR]

Structural colors are recognized as environmentally friendly colors compared with traditional pigments and dyes. However, their structural substrates are usually made of polymers or solid materials that are difficult to decompose naturally. Finding high‐performance bio‐degradable substrates is essential to protect the environment. Transparent wood paper is a competitive candidate because of its excellent biodegradability, high transparency, and strength. Here, it is firstly demonstrated that structural color prints can be fabricated monolithically on transparent wood paper. By mimicking the color generation structures in nature, nanostructures are imprinted on the surface of delignified wood and exhibit diverse structural colors. Three basic colors of red, green, and blue are demonstrated, and the colors can be continuously tuned by the periodicity and observation angle. Vivid color prints can be realized on the transparent wood paper by structural design. The structural colored transparent wood paper is flexible and bendable, and colors will not fade after 12‐month exposure to natural sunshine. Furthermore, the structural color prints on transparent wood paper are biodegradable and can be discarded directly after use. Both the structural colored relief and the transparent wood are eco‐friendly, opening a new door to next‐generation paper‐based disposable, sustainable, and green optical/photonic devices. [ABSTRACT FROM AUTHOR]

Enhanced supercontinuum generation (SCG) is experimentally demonstrated in integrated silicon nitride (Si3N4) waveguides incorporating highly nonlinear graphene oxide (GO) in the form of 2D films. On‐chip integration of the 2D GO films with precise control of their thickness is realized by using a transfer‐free and layer‐by‐layer coating method. The control of the film length and coating position is achieved via window opening in the upper silica cladding of the photonic integrated chips. Detailed SCG measurements are performed using the fabricated devices with different waveguide geometries and GO film thicknesses, and the results are compared with devices without GO. Significantly improved spectral broadening of ultrashort optical pulses with ultrahigh peak powers exceeding 1000 W is observed for the hybrid devices, achieving up to 2.4 times improvement in the spectral bandwidth relative to devices without GO. Theoretical analyses for the influence of GO film thickness, coating length, coating position, and waveguide geometry are also provided by fitting the experimental results with theory, showing that there is still significant room for further improvement. This work opens up a new avenue toward improving the SCG performance of photonic integrated devices by incorporating functional 2D materials. [ABSTRACT FROM AUTHOR]

Integrated photonic devices operating via optical nonlinearities offer a powerful solution for all‐optical information processing, yielding processing speeds that are well beyond that of electronic processing as well as providing the added benefits of compact footprint, high stability, high scalability, and small power consumption. The increasing demand for high‐performance nonlinear integrated photonic devices has facilitated the hybrid integration of novel materials to address the limitations of existing integrated photonic platforms. Recently, graphene oxide (GO), with its large optical nonlinearity, high flexibility in altering its properties, and facile fabrication processes, has attracted significant attention, enabling many hybrid nonlinear integrated photonic devices with improved performance and novel capabilities. This paper reviews the applications of GO to nonlinear integrated photonics. First, an overview of GO's optical properties and the fabrication technologies needed for its on‐chip integration is provided. Next, the state‐of‐the‐art GO nonlinear integrated photonic devices are reviewed, followed by comparisons of the nonlinear optical performance of different integrated platforms incorporating GO as well as hybrid integrated devices including different kinds of 2D materials. Finally, the current challenges and future opportunities in this field are discussed. [ABSTRACT FROM AUTHOR]

With compact footprint, low energy consumption, high scalability, and mass producibility, chip‐scale integrated devices are an indispensable part of modern technological change and development. Recent advances in 2D layered materials with their unique structures and distinctive properties have motivated their on‐chip integration, yielding a variety of functional devices with superior performance and new features. To realize integrated devices incorporating 2D materials, it requires a diverse range of device fabrication techniques, which are of fundamental importance to achieve good performance and high reproducibility. This paper reviews the state‐of‐art fabrication techniques for the on‐chip integration of 2D materials. First, an overview of the material properties and on‐chip applications of 2D materials is provided. Second, different approaches used for integrating 2D materials on chips are comprehensively reviewed, which are categorized into material synthesis, on‐chip transfer, film patterning, and property tuning/modification. Third, the methods for integrating 2D van der Waals heterostructures are also discussed and summarized. Finally, the current challenges and future perspectives are highlighted. [ABSTRACT FROM AUTHOR]

Layered 2D graphene oxide (GO) films are integrated with silicon nitride (SiN) waveguides to experimentally demonstrate an enhanced Kerr nonlinearity via four‐wave mixing (FWM). SiN waveguides with both uniformly coated and patterned GO films are fabricated based on a transfer‐free, layer‐by‐layer GO coating method along with standard photolithography and lift‐off processes, yielding precise control of the film thickness, placement, and coating length. Detailed FWM measurements are carried out for the fabricated devices with different numbers of GO layers and at different pump powers, achieving up to ≈7.3 dB improvement in the FWM conversion efficiency for an uniformly coated device with one layer of GO and ≈9.1 dB for a patterned device with five layers of GO. A detailed analysis of the influence of pattern length and position on the FWM performance is performed. The dependence of GO's third‐order nonlinearity on layer number and pump power is also extracted, revealing interesting physical insights about the layered 2D GO films. Finally, an enhancement is obtained in the effective nonlinear parameter of the hybrid waveguides by over a factor of 100 relative to bare SiN waveguide. These results demonstrate the high nonlinear optical performance of SiN waveguides integrated with layered 2D GO films. [ABSTRACT FROM AUTHOR]

Optical artificial neural networks (ONNs)—analog computing hardware tailored for machine learning—have significant potential for achieving ultra‐high computing speed and energy efficiency. A new approach to architectures for ONNs based on integrated Kerr microcomb sources that is programmable, highly scalable, and capable of reaching ultra‐high speeds is proposed here. The building block of the ONN—a single neuron perceptron—is experimentally demonstrated that reaches a high single‐unit throughput speed of 11.9 Giga‐FLOPS at 8 bits per FLOP, corresponding to 95.2 Gbps, achieved by mapping synapses onto 49 wavelengths of a microcomb. The perceptron is tested on simple standard benchmark datasets—handwritten‐digit recognition and cancer‐cell detection—achieving over 90% and 85% accuracy, respectively. This performance is a direct result of the record low wavelength spacing (49 GHz) for a coherent integrated microcomb source, which results in an unprecedented number of wavelengths for neuromorphic optics. Finally, an approach to scaling the perceptron to a deep learning network is proposed using the same single microcomb device and standard off‐the‐shelf telecommunications technology, for high‐throughput operation involving full matrix multiplication for applications such as real‐time massive data processing for unmanned vehicles and aircraft tracking. [ABSTRACT FROM AUTHOR]

ABSTRACT In the context of the global transition to renewable energy sources, the offshore wind power sector is confronted with operational inefficiencies during the thermal processing and assembly of wind turbine spindles and components. The research, centered on General Electric's offshore wind turbine assembly facility, addresses the deficiencies in the thermal management of bearing heating systems, the prevalence of rework due to substandard thermal treatments, and the inefficiencies in energy utilization. The paper proposes a targeted strategy comprising three key interventions: (1) The synchronization of bearing heating procedures with the off‐peak electricity tariff regime to mitigate peak demand and associated energy expenditures and carbon footprints. (2) The deployment of a thermoelectric generator (TEG) system to harness and convert waste heat into electrical energy, with meticulous modeling of its thermal dynamics. (3) The engineering of a thermally insulated housing for bearings to curtail thermal losses. The projected outcomes of these interventions are a reduction in electricity costs by 127.83 yuan, a decrease in carbon emissions by 90.41 kg, and a substantial reduction in heat loss. The findings of this research underscore the efficacy of thermal process optimization, waste heat recuperation, and thermal insulation in enhancing the energy efficiency of bearing heating systems, thereby contributing to the broader objectives of energy conservation and emission reduction in the renewable energy sector, which is imperative in the contemporary era of climate change mitigation and sustainable development. [ABSTRACT FROM AUTHOR]

Integrated waveguide polarizers and polarization‐selective micro‐ring resonators (MRRs) incorporated with graphene oxide (GO) films are experimentally demonstrated. CMOS‐compatible doped silica waveguides and MRRs with both uniformly coated and patterned GO films are fabricated based on a large‐area, transfer‐free, layer‐by‐layer GO coating method that yields precise control of the film thickness. Photolithography and lift‐off processes are used to achieve photolithographic patterning of GO films with precise control of the placement and coating length. Detailed measurements are performed to characterize the performance of the devices versus GO film thickness and coating length as a function of polarization, wavelength and power. A high polarization dependent loss of ≈53.8 dB is achieved for the waveguide coated with 2‐mm‐long patterned GO films. It is found that intrinsic film material loss anisotropy dominates the performance for less than 20 layers whereas polarization‐dependent mode overlap dominates for thicker layers. For the MRRs, the GO coating length is reduced to 50 µm, yielding a ≈8.3 dB polarization extinction ratio between transverse electric (TE) and transverse magnetic (TM) resonances. These results offer interesting physical insights and trends of the layered GO films and demonstrate the effectiveness of introducing GO films into photonic‐integrated devices to realize high‐performance polarization selective components. [ABSTRACT FROM AUTHOR]