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Co-processing of biomass feedstock with petroleum feedstock in existing refineries is a promising technology that enables the production of low-carbon fuels, reduces dependence on petroleum feedstock, and utilizes the existing infrastructure in refinery. Much effort has been dedicated to advancing co-processing technologies. Though significant progress has been made, the development of co-processing is still hindered by numerous challenges. Therefore, it is important to systematically summarize up-to-date research activities on co-processing process for the further development of co-processing technologies. This paper provides a review of the latest research activities on coprocessing biomass feedstock with petroleum feedstock utilizing fluid catalytic cracking (FCC) or hydrotreating (HDT) processes. In addition, it extensively discusses the influence of different types and diverse physicochemical properties of biomass feedstock on the processing of petroleum feedstock, catalysts employed in co-processing studies, and relevant projects. Moreover, it summarizes and discusses co-processing projects in pilot or larger scale. Furthermore, it briefly prospects the research trend of co-processing in the end. [ABSTRACT FROM AUTHOR]

Hydrogenolysis has been explored as a promising approach for plastic chemical recycling. Noble metals, such as Ru and Pt, are considered effective catalysts for plastic hydrogenolysis, however, they result in a high yield of low-value gaseous products. In this research, an efficient bimetallic catalyst was developed by separate impregnation of Ni and Ru on SiO2 support resulting in liquid products yield of up to 83.1 C % under mild reaction conditions, compared to the 65.5 C % yield for the sole noble metal catalyst. The carbon distribution of the liquid products from low density polyethylene hydrogenolysis with Ni-modified catalyst also shifted to a heavier fraction, compared to that with Ru catalyst. Meanwhile, the NiRu catalyst exhibited excellent performance in suppressing the cleavage of the end-chain C–C bond, leading to a methane yield of only 10.4 C %, which was 69% lower than that of the Ru/SiO2 catalyst. Temperature programmed reduction and desorption of hydrogen and propane were further conducted to reveal the detailed mechanism of low density polyethylene hydrogenolysis over the bimetallic catalyst. The results suggested that the Ni-Ru alloy exhibited stronger H adsorption properties indicating improved hydrogen coverage on the catalyst surface thus enhancing the desorption of reaction intermediates. The carbon number distribution was ultimately skewed toward heavier liquid products. [ABSTRACT FROM AUTHOR]

Septated pleural effusion is very common. The presence of septations in pleural effusion determines the local treatment strategy for such patients. Therefore, there is a pressing need for imaging techniques to assess the presence of septations. The objective of this research was to assess the diagnostic efficacy of computed tomography (CT) and chest ultrasound in identifying septated pleural effusion. We delineated the ultrasound and enhanced chest CT manifestations for diagnosing septated pleural effusions, and subsequently, we conducted a comparative analysis to assess the diagnostic efficacy of enhanced chest CT and ultrasound in identifying septated pleural effusions. Medical thoracoscopy served as the gold standard for confirming the diagnosis of septated pleural effusions. Ultrasound demonstrated a sensitivity of 82.6% (95% CI 73.3–89.7%) and a specificity of 100.0% (95% CI 98.1–NaN) for diagnosing septated pleural effusion. In comparison, enhanced chest CT exhibited a sensitivity of 59.8% (95% CI 49.0–69.9%) and a specificity of 87.0% (95% CI 81.5–91.4%). The positive predictive value for ultrasound was 100.0% (95% CI 95.3–100.0%), while for enhanced chest CT, it was 68.8% (95% CI 59.0–77.4%). Ultrasound yielded a negative predictive value of 92.3% (95% CI 87.5–NaN), and enhanced chest CT had a negative predictive value of 82.0% (95% CI 74.6–87.8%) in diagnosing septated pleural effusion. Thoracic ultrasound exhibits superior sensitivity and specificity compared to enhanced chest CT in diagnosing septated pleural effusions. Therefore, chest ultrasound is highly recommended as an adjunct for determining septated pleural effusion. [ABSTRACT FROM AUTHOR]

Catalytic fast pyrolysis (CFP) of biomass is a promising technology that can convert biomass into fuels. To understand how the metal oxides modified HZSM-5 catalysts enhance the formation of desirable hydrocarbons as well as suppress the coke formation during catalytic pyrolysis of lignocellulosic biomass, three types of metal (molybdenum (Mo), gallium (Ga), and tungsten (W)) oxides modified HZSM-5 catalysts were prepared. The activity of the catalysts was evaluated on a micro-reactor system. The effects of the atmosphere, metal oxide types, loading amounts of metal oxide, and catalysis temperature were all discussed. The introduction of hydrogen significantly enhanced the formation of hydrocarbons and decreased the coke formation. The yield of aliphatic products was further increased by 60%, while coke formation was suppressed by 52% using metal oxide-modified HZSM-5. Among these catalysts, HZSM-5 modified by molybdenum oxide obtained the highest hydrocarbon yield of 49.6%. HZSM-5 modified by gallium oxide obtained the highest aliphatic hydrocarbon yield of 30.4%. Compared to the control test using the HZSM-5 catalyst, coke yields were also decreased by 36%, 38%, and 35% for HZSM-5 modified by molybdenum oxide, gallium oxide, and tungsten oxide, respectively. HZSM-5 modified by molybdenum oxide was selected to further investigate the effects of loading amounts, catalysis temperature, and biomass to catalysts ratio. [ABSTRACT FROM AUTHOR]

As the basis work of image processing, rain removal from a single image has always been an important and challenging problem. Due to the lack of real rain images and corresponding clean images, most rain removal networks are trained by synthetic datasets, which makes the output images unsatisfactory in practical applications. In this work, we propose a new feature decoupling network for unsupervised image rain removal. Its purpose is to decompose the rain image into two distinguishable layers: clean image layer and rain layer. In order to fully decouple the features of different attributes, we use contrastive learning to constrain this process. Specifically, the image patch with similarity is pulled together as a positive sample, while the rain layer patch is pushed away as a negative sample. We not only make use of the inherent self-similarity within the sample, but also make use of the mutual exclusion between the two layers, so as to better distinguish the rain layer from the clean image. We implicitly constrain the embedding of different samples in the depth feature space to better promote rainline removal and image restoration. Our method achieves a PSNR of 25.80 on Test100, surpassing other unsupervised methods. [ABSTRACT FROM AUTHOR]

The investigation of the Al–Ag–Zr system is crucial for the development of heat-resistant Al alloys, which are essential for applications in high-temperature environments. In this work, we first determined the isothermal sections of the Al–Ag–Zr system at 500 and 600 °C using equilibrium alloys. Simultaneously, the τ3 (Al6AgZr6) phase was identified by transmission electron microscopy (TEM). In addition, the three-phase equilibrium of τ3 + AgZr + (Ag) instead of Al3Zr4 + AgZr + (Ag) was confirmed at 500 and 600 °C. The formation enthalpies of the end-members and ternary compounds in the Al–Ag–Zr system were calculated via first-principles calculations. Based on the experimental and computational results, a thermodynamic database of the Al–Ag–Zr system was established using the CALPHAD (calculation of phase diagrams) method. The hardness of τ1 (Al2.68Ag0.32Zr) and τ2 (Al1.84Ag0.16Zr) were determined to be 3.82 and 10.20 GPa, respectively, using nanoindentation. The introduction of the τ2 phase in the design of Al alloys can considerably increase the mechanical properties of the alloys. [ABSTRACT FROM AUTHOR]

With rapid socioeconomic and population growth, high-quality arable land resources are decreasing daily, especially in arid areas, which makes arable land reserve resources an important way to supplement arable land. How to accurately evaluate cultivated land reserve resources is of great significance to socioeconomic development and sustainable land use in arid areas. Therefore, this study selected Hangjin Banner as a typical area and calculated the regional maximum available irrigation water based on the principle of regional water balance. Then, the "irrigation area check algorithm" was used to evaluate the amount of cultivated land reserve resources, and policy recommendations were proposed for the development and utilization of cultivated land resources. The results showed that Hangjin Banner had no cultivated land reserve resources under the current irrigation method and had cultivated land reserve resources under the efficient water-saving irrigation method, but only in the southern zone during normal and partially abundant water years. Therefore, we believe that arid areas should adhere to the "set land by water" principle, the allocation of water resources should be optimized, and cultivated land resources with high quality should be utilized based on the actual regional conditions. [ABSTRACT FROM AUTHOR]

In this work, the polarized beams tightly focused through a cylindrical refractive-indices discontinuous dielectric interface was numerically investigated. The corresponding focal pattern calculation formula was deduced base on vectoral diffraction integration theory for the first time. The patterns through the cylindrical dielectric interface with different radii were revealed by numerical calculating and discussed in detail. In addition, the aberration factor of the integration formula was found out, and the phase compensation maps were successfully carried out for focal patterns correcting. The findings will be helpful to improve the spatial resolution of advanced optical microscope in probing samples encapsulated by micro pipes. [ABSTRACT FROM AUTHOR]

Aspect-based sentiment analysis can predict the sentiment polarity of specific aspect terms in the text. Compared to general sentiment analysis, it extracts more useful information and analyzes the sentiment more accurately in the comment text. Many previous approaches use long short-term memory networks with attention mechanisms to directly learn aspect-specific representations and model comment text. However, these methods always ignore the importance of the aspect terms position and interactive information between the aspect terms and other words. To address these issues, we propose an improved model based on convolutional neural networks. First, a novel relative position encode layer can integrate the relative position information of specific aspect terms validly in a text. Second, by using the aspect attention mechanism, the semantic relationship between aspect terms and words in the text is fully considered. To verify the effectiveness of the proposed models, we conduct a large number of experiments and comparisons on seven public datasets. The experimental results show that this model outperforms to other state-of-the-art methods. [ABSTRACT FROM AUTHOR]

Dye wastewater has been becoming the focus of environmental protection and scientific research because of its serious harm to the environment and living organisms. A supported nano-porous anode alumina-NiO (nano-PAA-NiO) photocatalyst was prepared by calcining nano-PAA-NiCl2 composite which was grown with a self-organization method. Its morphology and composition were investigated by means of SEM, EDS, and XRD. The specific surface area of nano-PAA-NiO was characterized with the N2 adsorption and desorption isotherms. The band gap was calculated to be 3.0 eV with the UV–Vis absorption spectra. The species and optical properties of nano-PAA-NiO were investigated by FT-IR spectra and photoluminescence spectra. With the nano-PAA-NiO photocatalyst, the degradation rates of methyl orange (MO) were 94.3% under the optimum conditions, and it could reach 82% when the catalyst was reused for the third time. In addition, the photocatalytic mechanism was proposed, and the reactions followed the Langmuir–Hinshelwood model. The nano-PAA-NiO composite has an excellent effect for organic dye wastewater treatment and practical prospects in environmental protection. [ABSTRACT FROM AUTHOR]

Confocal Raman microspectral imaging (CRMI) is an advanced cell-imaging method that maps endogenous molecular compositions with their unique spectral fingerprint indicators. The aim of this work was to provide a visualized understanding of subcellular features of live osteosarcoma cells using a 532-nm laser excitation without the use of dyes or molecular probes. Both malignant osteoblast and spindle osteosarcoma cells derived from the BALB/c mouse osteosarcoma cell line K7M2 were investigated in this work. After preprocessing the obtained spectral dataset, K-means cluster analysis (KCA) is employed to reconstruct Raman spectroscopic maps of single biological cells by identifying regions of the cellular membrane, cytoplasm, organelles, and nucleus with their corresponding mean spectra. Principal component analysis (PCA) was further employed to indicate variables of significant influence on the separation of the spectra of each cellular component. The biochemical components of the two cell types were then extracted by showing the spectral and distribution features attributed to proteins, lipids, and DNA. Using this standardized CRMI technique and multivariate analysis approaches, the results obtained could be a sound foundation for a typical Raman imaging protocol of live cellular biomedical analysis. [ABSTRACT FROM AUTHOR]

Dye wastewater treatment has been a hot spot of scientific research and technological development. One kind of porous CuCl2 film with controllable three-dimensional structure was synthesized on the top surface of nanoporous anodic alumina (nano-PAA) by self-assembled method. The nano-PAA-CuCl2 film and H2O2 form a heterogeneous Fenton-like catalytic system, and the catalysts were characterized by EDS, XPS and FE-SEM. Then, the main parameters affecting the degradation of Rhodamine B (RhB) were investigated in detail. Under the optimum experimental conditions, i.e., initial pH 3.3, initial H2O2 concentration 14 mmol/L, nano-PAA-CuCl2 generated with 8 × 10−4 mol/L CuCl2 solution, RhB was completely degraded four times. Even the degradation rates were still as high as 97.1% and 94.8% when the nano-PAA-CuCl2 catalyst was reused for the fifth and sixth times, respectively. In addition to enhancing the catalytic activity, the pH of the treated solution had a wide range value, i.e., 2-8, with an optimal value of 5.8. At last in the paper, a degradation mechanism of heterogeneous Fenton-like catalytic degradation of RhB by nano-PAA-CuCl2/H2O2 system is proposed, the reaction kinetics accorded with the pseudo-first-order equation. All the results indicate that the nano-PAA-CuCl2 has practical prospects for H2O2-driven Fenton-like treatment of organic dye wastewater, with the advantages of green and cost-effective, stability and reusability. [ABSTRACT FROM AUTHOR]

Confocal Raman microspectral imaging (CRMI) provides a versatile tool to extract biochemical information on histologically defined regions with improved spatial resolution and sensitivity. Here, we investigate spectral features and perform both uni- and multivariate analyses to obtain precise correlation between the biochemical profile and histological architecture of ex vivo human skin tissue. The skin dermis layer is visualized by integrated images of collagen peaks at 855, 940, and 1248 cm−1, while the stratum corneum layer is described by chemical images of ceramides. M elanin accumulation patterns in epidermis are obtained by integration of 1375 and 1580 cm−1 Raman peaks. In addition, distinct spectral features of the melanin precursor are revealed by certain Raman vibrations, which structurally characterize the molecular composition and organization of hair follicles. These results offer a unique insight into the skin histology, biochemistry, and biophysics, which provide the possibility of interpreting the underlying mechanisms of skin malignant processes. [ABSTRACT FROM AUTHOR]

Phospholipase C epsilon 1 (PLCE1) has been recognized as a novel susceptibility marker for esophageal squamous cell carcinoma (ESCC). The purpose of our study is to investigate its effect on the regulation of miRNA expression so as to translating the data into a novel strategy in control of ESCC. In this study, PLCE1 siRNA and vector-only plasmid were stably transfected into Eca109 and EC9706 cells and then subjected to miRNA array analysis, and quantitative real-time PCR was applied to validate miRNA array data. Then bioinformatic analyses, such as GO and pathway software, were conducted to obtain data on these differentially expressed miRNAs-targeted genes (DEGs) and clarify their function and pathway. The results showed that 36 miRNAs were found to be differentially expressed in PLCE1 siRNA-transfected cells compared with the control cells. In particular, 28 miRNAs were upregulated while 8 miRNAs were downregulated. Gene Ontology analysis showed that the function of the DEGs included cell cycle arrest, cell-matrix adhesion, apoptosis, etc. After this, the major pathways associated with the DEGs were regulation of actin cytoskeleton, TGF-beta signaling pathway, Notch signaling pathway and so on. Taken together, these results showed that the knockdown of PLCE1 may play a vital role in the control of ESCC. Further investigation will reveal and verify the function and pathway of the DEGs for the development of novel treatment strategy for the better control of ESCC. [ABSTRACT FROM AUTHOR]

The composite structure of nano-porous anodic alumina (nano-PAA) coated with noble metal layer has been demonstrated to be one kind of high-sensitive surface-enhanced Raman scattering (SERS)-active substrate. However, the experimental investigations on influences of parameters were restricted by correlation between variables. And in relevant simulation studies, nano-tips at intersections of unit edges on the surface and the metal attaching to inside walls of nano-holes which are crucial for the enhancement of electric field were commonly idealized. To obtain the optimal structure of nano-PAA-Au array for SERS applications, numerical evaluations of the electric field distributions and intensities at hotspots were carried out on a proposed precise model. The influence of structure and excitation parameters which determined the electromagnetic enhancement have been systematically investigated. The numerical data shows that the intensity and distribution of surface electric field is evidently affected by both the characteristics of nano-tips and the metal attaching to the inside wall of holes. In addition, the designed substrate was synthesized accordingly and demonstrated to be higher sensitive with an achieved enhancement factor of 1.04 × 107. The study would be helpful in designing high-sensitive SERS-active substrates. [ABSTRACT FROM AUTHOR]

In the research of bio-molecular chips and sensors, extra electric biases are most often employed to control and manipulate the DNA and protein molecules moving through micro/nano-fluidic channels. In order to accurately and flexibly control the bio-molecules as they move within the channels, a clear understanding of how the current changes within the buffer solution caused by an applied bias is fundamental. In this report, the current changed value of different buffer solutions, e.g., KCl, TE, and TBE was systematically studied with real-time monitoring and quantitative analysis in the situation of the buffers moving through a fluidic channel with a 5 μm inner diameter, driven by biases of 50 or 100 mV. The results revealed that the relationship between the current changed value and the pause interval of the applied electric field is highly consistent with the Hill Equation, which is helpful for accurately detecting and manipulating single biomolecules in microfluidic sensors and biochips. [ABSTRACT FROM AUTHOR]

The porous anodic alumina membranes (PAAMs) have been successfully used as templates for the fabrication of functional nano-materials due to their outstanding regularity and physicochemical properties. In this paper, a transparent double-sided anodic alumina membrane with ultra-thin aluminum substrate was fabricated with the three-step anodic oxidation method in the oxalic acid electrolyte. The characters such as the top-surface morphology, membrane thickness, and depth of nanopores of this three-layer (AlO-Al-AlO) sandwiched nano-structure were controllable through regulating the main anodic oxidation conditions, e.g., anodic oxidation time of various steps, coating remove process. The experiments data revealed that the aluminum substrate is exponential declined with the oxidation time when it was approximately reduced by a few micrometers. This new double-sided anodic alumina membrane can be used as the high-quality functional field emission materials and templates. [ABSTRACT FROM AUTHOR]

Based on the Van Soest method, the components in Chinese fir and fast-growing poplar were quantified, and the fiber present was separated into three fractions: neutral detergent fiber, acid detergent fiber and strong acid detergent fiber. Microstructure of the fibers was investigated by a Fourier transform infrared spectrometry. Cellulose and hemicellulose both represent the characteristics of polysaccharides, while lignin has dissimilar structure. Pyrolysis of fir, poplar and the detergent fibers was carried out on a thermogravimetric analyzer coupled with FTIR spectrometry. After the removal of extractives and soluble minerals, pyrolysis of NDF shows the characteristics of the three main components. Hydrocarbons, aldehydes, ketones, acids, alcohols and others are generated due to the primary pyrolysis of hemicellulose and cellulose in single stages. Phenols and alcohols are the dominant volatiles released from pyrolysis of lignin in two successive stages, respectively. [ABSTRACT FROM AUTHOR]

We study a four-level double-Λ atomic ensemble interacting with two time-dependent signal fields and two stationary control fields. Though, in each Λ channel, a pair of signal and control fields couple resonantly with the two lower levels of atoms, the occurrences of electromagnetically induced transparency (EIT) is affected by the coherence of the four fields. In the discussion of atomic susceptibilities, we show that the quantum coherence between the two lower levels can be either formed or released according to the phase matching of the four fields. We analyze the propagation equation of the two signal fields, and find two characteristic solutions: the stationary transmission wave and the transient decay wave. The former corresponds to a correlated EIT effect in which two signal pulses are shape-matched. The latter is an opposite effect to the correlated EIT in which two pulses quench simultaneously, thus named as the correlated two-signal absorption (CTSA). We propose the CTSA condition in correspondence with the EIT condition. The numerical simulation shows that the double-Λ configuration is capable of manipulating synchronous optical signals and thus provides multiplicity and versatility in quantum information process. [ABSTRACT FROM AUTHOR]

We present a complete theoretical description of atomic storage states in the multimode framework by including spatial coherence in atomic collective operators and atomic storage states. We show that atomic storage states are Dicke states with the maximum cooperation number. In some limits, a set of multimode atomic storage states has been established in correspondence with multimode Fock states of the electromagnetic field. This gives better understanding of both the quantum and coherent information of optical field can be preserved and recovered in ultracold medium. In this treatment, we discuss in detail both the adiabatic and dynamic transfer of quantum information between the field and the ultracold medium. [ABSTRACT FROM AUTHOR]

In most electrokinetic flows in micro-/nanofluidics, electroosmotic flow (EOF) is always a fundamental phenomenon. When an external AC electric field is applied, there will be a transient EOF velocity, which is crucial for understanding the mechanism of the unsteady AC EOF. However, the transient flow velocity cannot be experimentally measured with sufficiently and simultaneously temporal and spatial resolution. Here we report that under a strong AC electric field, an asymmetric temporal variation of oscillating EOF (OEOF) can be generated near the electric double layer (EDL) on the bottom wall of a microchannel. The flow is measured by laser-induced fluorescence photobleaching anemometer (LIFPA). Both the flow velocity of the OEOF and the linearly related internal electric field in the microchannel are theoretically governed by an inviscid Burgers' equations with an external forcing term and controlled by two coefficients which represent the magnitudes of linear ( Z l ) and nonlinear ( Z nl ) terms. These two coefficients are separately determined by five dimensionless parameters, including Stokes number ( St ), aspect ratio (γ ), Schmidt number ( Sc ), Peclet number of mean flow velocity ( P e , U ) and Peclet number of electrophoresis ( P e , EP ). In this work, the influence of P e , U and P e , EP which are tightly related to the local mean flow velocity and the amplitude of AC electric field is investigated. When the electric field is low, P e , U ≫ P e , EP and accordingly Z l ≫ Z nl , a temporal symmetry of the time series of velocity is observed. However, when the electric field is high, P e , U ≪ P e , EP and Z l ≪ Z nl , then the periodicity and temporal symmetry of OEOF can be significantly broken and a temporal asymmetry of the time series of velocity is resulted in, especially under the square wave external electric field. We also find increased mean flow velocity and saturation of velocity fluctuations with the increasing electric field. This work provides a new methodology to study unsteady electrokinetic flows. [ABSTRACT FROM AUTHOR]

The COVID-19 outbreak is becoming a public health emergency. Data are limited on the clinical characteristics and causes of death. A retrospective analysis of COVID-19 deaths were performed for patients' clinical characteristics, laboratory results, and causes of death. In total, 56 patients (72.7%) of the decedents (male–female ratio 51:26, mean age 71 ± 13, mean survival time 17.4 ± 8.4 days) had comorbidities. Acute respiratory failure (ARF) and sepsis were the main causes of death. Increases in C-reactive protein (CRP), lactate dehydrogenase (LDH), D-dimer and lactic acid and decreases in lymphocytes were common laboratory results. Intergroup analysis showed that (1) most female decedents had cough and diabetes. (2) The proportion of young- and middle-aged deaths was higher than elderly deaths for males, while elderly decedents were more prone to myocardial injury and elevated CRP. (3) CRP and LDH increased and cluster of differentiation (CD) 4+ and CD8+ cells decreased significantly in patients with hypertension. The majority of COVID-19 decedents are male, especially elderly people with comorbidities. The main causes of death are ARF and sepsis. Most female decedents have cough and diabetes. Myocardial injury is common in elderly decedents. Patients with hypertension are prone to an increased inflammatory index, tissue hypoxia and cellular immune injury. [ABSTRACT FROM AUTHOR]

As a novel velocity measurement technique for micro/nanofluidics applications, the laser-induced fluorescence photobleaching anemometer (LIFPA) has been proven to have simultaneously high spatial and temporal resolutions. Its temporal resolution, which is crucial for investigations of transient flows, is directly determined by the photobleaching time constant. In this study, the factors, e.g., fluorescent excitation and emission spectra and the photobleaching time constant that may affect LIFPA measurements, were investigated using the coumarin 102 fluorescent dye at different concentrations (10–300 μM) in a confocal-microscope-based system. We report that a blue shift of the emission spectrum in the range of 430–515 nm can be observed during photobleaching attributed to the photochemical reactions between coumarin 102 molecules. Meanwhile, different photobleaching time constants are also observed in different bands of the emission spectrum. All of the photobleaching time constants are below 3 μs, which is nearly an order smaller than the previously reported values. Among all of the spectral bands, the bands at 470–492 nm can provide a higher fluorescent intensity and better accuracy for velocity measurements. The bands at 430 and 460 nm can provide a higher temporal resolution. [ABSTRACT FROM AUTHOR]