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Analyzes the refuse compositions and settlement in large-scale landfill in Shanghai, China. Stabilization process and reuse approaches for landfills; Construction of the experimental landfill unit; Settlement of refuse surface and mathematical simulation.

Context: Due to their excellent biocompatibility and degradability, cellulose/spider silk protein composites hold a significant value in biomedical applications such as tissue engineering, drug delivery, and medical dressings. The interfacial interactions between cellulose and spider silk protein affect the properties of the composite. Therefore, it is important to understand the interfacial interactions between spider silk protein and cellulose to guide the design and optimization of composites. The study of the adsorption of protein on specific surfaces of cellulose crystal can be very complex using experimental methods. Molecular dynamics simulations allow the exploration of various physical and chemical changes at the atomic level of the material and enable an atomic description of the interactions between cellulose crystal planes and spider silk protein. In this study, molecular dynamics simulations were employed to investigate the interfacial interactions between spider silk protein (NTD) and cellulose surfaces. Findings of RMSD, RMSF, and secondary structure showed that the structure of NTD proteins remained unchanged during the adsorption process. Cellulose contact numbers and hydrogen bonding trends on different crystalline surfaces suggest that van der Waals forces and hydrogen bonding interactions drive the binding of proteins to cellulose. These findings reveal the interaction between cellulose and protein at the molecular level and provide theoretical guidance for the design and synthesis of cellulose/spider silk protein composites. Methods: MD simulations were all performed using the GROMACS-5.1 software package and run with CHARMM36 carbohydrate force field. Molecular dynamics simulations were performed for 500 ns for the simulated system. [ABSTRACT FROM AUTHOR]

In examining the dynamic behavior and fracturing mechanism of granite using numerical simulation methods, many studies assume a random distribution of minerals, which fails to accurately represent the actual distribution. The primary objects of this study are therefore to combine digital image processing (DIP) method with the discrete element method (DEM) to develop a more accurate granite model that matches the real mineral distribution of the granite specimen. The DEM is then used to simulate the Split Hopkinson Pressure Bar (SHPB) test, exploring how mineral properties like mineral content, grain shape, grain size, and loading conditions such as strain rate and confining pressure, affect the dynamic behavior and fracture pattern of granite. The results demonstrate that granite models, despite differing grain shapes and sizes, display similar dynamic strength (varying by 4.8%) when they have comparable mineral contents. Feldspar content significantly affects stress variations, while quartz and biotite have minor impact. Stronger minerals like quartz and feldspar show similar fracture patterns, whereas biotite leads to a larger damage area and denser fracture distribution. Loading conditions, such as strain rate and confining pressure, significantly influence the fracture behavior of granite specimens. Fracture propagation is primarily characterized by tension cracks, with shear cracks following, and their distribution varies based on mineral properties and loading conditions. • Combined DIP and DEM methods for accurate granite modeling. • Explored how mineral and loading conditions affect granite dynamics. • Quantitatively analyzed the fracturing mechanism of granite. [ABSTRACT FROM AUTHOR]

Giving Timely warnings for fire is very crucial for fire prevention and the protection of people's lives and property. However, most current fire warning sensors give warnings above 200 °C, which are not conducive to efficient and accurate warnings. Therefore, it is important to develop high-temperature sensors that can give timely, portable warnings at low temperatures (100 to 200 °C). Herein, simple and portable nonopen flame thermochromic photonic crystal (PC) stickers were constructed using ZnS nanoparticles and polyethylene (PE) films as the main components. The structural color of the PC stickers changed due to the chain motion of PE chain, and the changement of the refractive index of the materials when heating. Thus, an early fire warning sensor (EFWS) was designed based on the structural color change of PC stickers. The EFWS can give timely and visible sensing in 0.8 s at 115 °C. The EFWS based on PC stickers can be combined with indoor surveillance cameras for nonopen fire warnings and key place monitoring (e.g., electrical equipment) in households, aircraft, electrical appliances, substations, etc.

Cellulose/collagen composites have been widely used in biomedicine and tissue engineering. Interfacial interactions are crucial in determining the final properties of cellulose/collagen composite. Molecular dynamics simulations were carried out to gain insights into the interactions between cellulose and collagen. It has been found that the structure of collagen remained intact during adsorption. The results derived from umbrella sampling showed that (110) and ([Formula: see text]) faces exhibited the strongest affinity with collagen (100) face came the second and (010) the last, which could be attributed to the surface roughness and hydrogen-bonding linkers involved water molecules. Cellulose planes with flat surfaces and the capability to form hydrogen-bonding linkers produce stronger affinity with collagen. The occupancy of hydrogen bonds formed between cellulose and collagen was low and not significantly contributive to the binding affinity. These findings provided insights into the interactions between cellulose and collagen at the molecular level, which may guide the design and fabrication of cellulose/collagen composites., (© 2022. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

A new 2(3 --> 20)abeotaxane with an unusual 13beta-substitution pattern and a new 6/8/6-ring taxane were isolated from the methanol extract of the needles of Taxus cuspidata. The structures were established as 2alpha,7beta-diacetoxy-5alpha,10beta,13beta-trihydroxy-2(3 --> 20)abeotaxa-4(20), 11-dien-9-one (1) and 2alpha,5alpha,7beta,9alpha,13alpha-pentahydroxy-10beta-acetoxytaxa-4(20),11-diene (2) on the basis of 1D and 2D NMR spectral data and high-resolution FAB-MS analyses., (Copyright 2007 John Wiley & Sons, Ltd.)

A new taxane glycoside was isolated from a methanol extract of the needles of Taxus cuspidata. The structure was established as 2alpha,9alpha,10beta-triacetoxytaxa-4(20),11-dien-13-one-5alpha-O-beta-D-glucopyranoside (1) on the basis of 1D- and 2D NMR and high-resolution fast atom bombardment mass spectral analyses., (Copyright 2005 John Wiley & Sons, Ltd.)