Colonization of biofilm in wastewater treatment: A review.

The attachment and colonization process of microorganisms on a carrier is an interdisciplinary research field. Through a series of physical, chemical, and biological actions, the microorganisms can eventually reproduce on the carrier. This article introduces biofilm start-up and its applications, and explores the current issues to look forward to future development directions.

Pore Structural Features of Granite under Different Temperatures.

To explore the effects of thermal actions on the pore structural features of granite, scanning electron microscope (SEM) and mercury injection experiments were carried out on granite after thermal treatment (25 °C to 400 °C). The pore structure was investigated from various perspectives, including the capillary pressure curve, the pore-throat ratio, the median saturation pressure, the median pore-throat radius, the porosity, the pore volume, and the pore size distribution. Based on mercury intrusion test data, the Winland model of permeability prediction was modified for a high-temperature tight granite reservoir.

Understanding the synergistic mechanism of PAM-FeCl for improved sludge dewaterability.

Hybrid flocculant polyacrylamide-ferric chloride (PAM-FeCl) was developed to improve the dewaterability of sewage sludge and the dewatering performance, properties of treated sludge, composition and morphology distribution of extracellular polymeric substance (EPS) were investigated. The physicochemical properties of the PAM-FeCl were characterized, and its effectiveness as a sludge conditioner was evaluated. The results indicated that PAM-FeCl conditioning was able to promote sludge dewaterability.

Enhance pore structure of cyanobacteria-based porous carbon by polypropylene to improve adsorption capacity of methylene blue.

Porous carbon obtained by co-pyrolysis of plastic and biomass has received a lot of attention due to its excellent adsorption properties, and the pore structure plays an essential role in adsorption performance, however, the pore structure is still not well understood. Herein, we synthesized cyanobacteria-based porous carbon derived from cyanobacteria and polypropylene plastic by one-step method. CPC-800-30% exhibited a high BET surface area (2140 m/g), pore volume up to 1.

Spatiotemporal evolution law and driving force of mining city patterns.

Urban transformation is an inevitable trend for mining cities to achieve sustainable development. Analyzing the spatiotemporal evolution laws and driving mechanisms of mining cities is necessary for providing a scientific basis for their transformation. In this study, Jixi was taken as an example, which is a typical mining city in China.

Evaluating Spatiotemporal Distribution of Residential Sprawl and Influencing Factors Based on Multi-Dimensional Measurement and GeoDetector Modelling.

Residential sprawl constitutes a main part of urban sprawl which poses a threat to the inhabitant environment and public health. The purpose of this article is to measure the residential sprawl at a micro-scale using a case study of Hangzhou city. An integrated sprawl index on each 1 km × 1 km residential land cell was calculated based on multi-dimensional indices of morphology, population density, land-use composition, and accessibility, followed by a dynamic assessment of residential sprawl.

Stability and Hopf Bifurcation Analysis of an Epidemic Model with Time Delay.

Epidemic models are normally used to describe the spread of infectious diseases. In this paper, we will discuss an epidemic model with time delay. Firstly, the existence of the positive fixed point is proven; and then, the stability and Hopf bifurcation are investigated by analyzing the distribution of the roots of the associated characteristic equations.

Raman Spectroscopy Study on Ternary Model Coal Mine Methane Hydrates.

The microfeatures of coal mine methane (CMM) hydrates, synthesized with three gas samples (CH/CH/N, G1 = 43 : 47 : 10, G2 = 60 : 30 : 10, and G3 = 74 : 16 : 10) in a self-made transparent high-pressure cell at 275.15 K and 5 MPa were investigated using Raman spectroscopy. As a discriminator, the vibrational band frequencies in the C-C regions of the recorded hydrate Raman spectra for CH show that G1∼G3 hydrates are structure I.

Experimental Investigation of the Attachment Performance between Coal Particle and Bubble.

Attachment behavior is a key component of flotation and has a decisive influence on flotation performance, and the experiment research on the attachment between mineral particles and bubbles still needs further research. In this work, a particle-bubble attachment apparatus and multiple target tracking software were developed. Coal particles were used as the subjects, and the effect of particle properties on the attachment performance was studied from the perspective of the particle group.

Synergistic effect of cocatalytic NiSe on stable 1T-MoS for hydrogen evolution.

Robust and economical catalysts are imperative to realize the versatile applications of hydrogen. Herein, a 1T-MoS/N-doped NiSe composite was rationally synthesized a solvothermal method, in which the MoS nanosheets have a stable 1T phase structure, and the NiSe nanoparticles serve as a cocatalytic support for MoS. The nonnegligible electronic couplings between NiSe and MoS could facilitate the optimization of their electronic structure and then improve the hydrogen adsorption.

Biohydrogen production from traditional Chinese medicine wastewater in anaerobic packed bed reactor system.

Three anaerobic packed bed reactors (APBR) packed with activated carbon, maifanite and tourmaline as support material were continuously operated for 165 days to generate hydrogen from traditional Chinese medicine wastewater at different organic loading rates (OLR) from 15.2 to 91.3 g COD L d by changes of hydraulic retention time (HRT) varying from 24 to 6 h.

Kinetics of Hydrate Formation and Dissociation in Coal at Different Temperatures Based on Impedance Method.

In the process of coal mining, gas outburst is a challenge that must be prevented to guarantee mining safety. Forming gas hydrate in coal can reduce the original gas pressure and delay the concentrative outbursts of gas flow, which is one of the potential technologies to prevent gas outbursts in coal. In this work, we perform the formation and dissociation kinetics experiment of hydrate in the presence of coal and tetrahydrofuran (THF) at the temperature based on different geological conditions in China by means of the experimental device with the impedance measurement function.

Modeling and predicting city-level CO emissions using open access data and machine learning.

Globally, urban has been the major contributor to greenhouse gas (GHG) emissions and thus plays an increasingly important role in its efforts to reduce CO emissions. However, quantifying city-level CO emissions is generally a difficult task due to lacking or lower quality of energy-related statistics data, especially for some underdeveloped areas. To address this issue, this study used a set of open access data and machine learning methods to estimate and predict city-level CO emissions across China.

Vertical distance from shading in the SEM.

Vertical data collected by Scanning Electron Microscopy (SEM) are important for sample characterization, 3D reconstruction, and flex manipulation. Traditional methods are limited by the extent to which the probe obstructs the view of the sample along the vertical axis. Herein, we propose a novel SEM microprobe for measuring the vertical distance between the probe and substrate.

Analysis of Developmental Characteristics and Dominant Factors of Pore-Fracture Systems in Lower Cambrian Marine Shale Reservoirs: A Case Study of the Niutitang Formation, Fenggang Block, Southern China.

Due to breakthroughs in the Lower Silurian Longmaxi Formation in the Sichuan Basin and multiple strata around the basin, the northern part of Guizhou adjacent to the Sichuan Basin has become a key area for shale gas exploration. Compared with the Longmaxi Formation, the Niutitang Formation displays greater TOC (total organic carbon) content, depositional thickness and distribution area, but the details remain undetermined. In the study area, the Lower Cambrian Niutitang Formation typically has high TOC content, maturity and brittle mineral content.

Esterification modified starch by phosphates and urea via alcohol solvothermal route for its potential utilization for urea slow-releasing.

The natural starch (NS) is modified by an esterification process which is accomplished by reacting the NS and phosphate together with urea via a facile alcohol solvothermal method. After modification, a series of obvious variations can be easily confirmed for the resulted starch phosphate carbamides (denoted as SPC) compared with that of NS, such as the introduction of new groups of CO, PO, P-O-C and P-O-H together with new elements of N and P in starch molecular structure unit confirmed in FT-IR and XPS analyses and the decreased crystallinity along with formed surface defect demonstrated in XRD and SEM measurements. Furthermore, the formed SPC has a higher viscosity of 480 mPa.

Construction of Molecular Model and Adsorption of Collectors on Bulianta Coal.

To study the effects of different oxygen functional groups on the quality of flotation clean low-rank coal, two kinds of collectors with different oxygen-containing functional groups, methyl laurate, and dodecanol, were selected and their flotation behaviors were investigated. The Bulianta coal was the typical sub-bituminous coal in China, and the coal molecular model of which was constructed based on proximate analysis, ultimate analysis, C-NMR, and XPS. The chemical structure model of the coal molecule was optimized, and the periodic boundary condition was added via the method of molecular dynamics methods.

The adsorption mechanisms of algae-bacteria symbiotic system and its fast formation process.

The formation process of the algae-bacteria symbiotic system (ABSS) was analyzed, and the formation adsorption conditions were optimized. The role of extracellular polymeric substances (EPS), specific surface area and zeta potential in adsorption mechanisms were assessed and proposed. The results showed the dry weight of the ABSS and adsorption efficiency of microalgae reached the highest under the conditions of 25 °C, pH 6.

pulseTD: RNA life cycle dynamics analysis based on pulse model of 4sU-seq time course sequencing data.

The life cycle of intracellular RNA mainly involves transcriptional production, splicing maturation and degradation processes. Their dynamic changes are termed as RNA life cycle dynamics (RLCD). It is still challenging for the accurate and robust identification of RLCD under unknow the functional form of RLCD.

Self-propelled torus colloids.

Suspensions of chemically powered self-propelled colloidal particles are examples of active matter systems with interesting properties. While simple spherical Janus particles are often studied, it is known that geometry is important and recent experiments have shown that chemically active torus-shaped colloids behave differently from spherical colloids. In this paper, coarse-grained microscopic simulations of the dynamics of self-diffusiophoretic torus colloids are carried out in bulk solution in order to study how torus geometric factors influence their active motion.

Gene Expression and K Uptake of Two Tomato Cultivars in Response to Sub-Optimal Temperature.

Sub-optimal temperatures can adversely affect tomato () growth, and K plays an important role in the cold tolerance of plants. However, gene expression and K uptake in tomato in response to sub-optimal temperatures are still not very clear. To address these questions, one cold-tolerant tomato cultivar, Dongnong 722 (T722), and one cold-sensitive cultivar, Dongnong 708 (S708), were exposed to sub-optimal (15/10 °C) and normal temperatures (25/18 °C), and the differences in growth, K uptake characteristics and global gene expressions were investigated.

Enhancement of flaky graphite cleaning by ultrasonic treatment.

In this study, the aim is to simplify the graphite cleaning process. In order to achieve flotation for graphite effectively, ultrasonic treatment was used as a pre-treatment technique. Flotation tests were conducted using different ultrasound power and ultrasonic treatment time.

Continuous hydrogen and methane production from the treatment of herbal medicines wastewater in the two-phase 'UASB-IC' system.

A two-phase anaerobic system comprised of upflow anaerobic sludge bed (UASB) reactor for hydrogen production and internal circulation reactor (IC) for methane production was proposed and investigated at laboratory scale and mesophilic temperature (35 °C). Hydrogen was efficiently produced from the UASB with the highest production rate of 3.00 ± 0.

Comparison of Three Algorithms for the Retrieval of Land Surface Temperature from Landsat 8 Images.

The successful launch of the Landsat 8 satellite provides important data for the monitoring of urban heat island effects. Since the Landsat 8 TIRS data has two thermal infrared bands, it is suitable for many algorithms to retrieve the land surface temperature (LST). However, the selection of algorithms for retrieving the LST, the acquisition of algorithm input parameters, and the verification of the results are problems without obvious solutions.

Probing the "Gas Tunnel" between Neighboring Nanobubbles.

Surface nanobubbles are the main gaseous domains forming at solid-liquid interfaces, and their abnormally long lifetime (stability) is still an open question. A hypothesis "gas tunnel" was presented in a recent simulation study [ , (3), 2603-2609], which was thought to connect two neighboring nanobubbles and make the nanobubbles remain stable. Herein, we aim to experimentally investigate the existence of gas tunnel and its role in governing nanobubble dynamics.