Inorganic Gases Research Articles

Annealing-induced enhancement of TiO2-ZnO nanocomposites for high-performance room-temperature air pollutant detection in fiber optic sensors

Fiber optic sensors, promising for their compactness and remote sensing abilities, are explored in this study as a platform for detecting volatile organic compounds (VOCs) using nanocrystalline metal oxide composites like TiO2-doped ZnO. Hydrothermally synthesized (S1 sample)and annealed composites (500 °C (S2 sample) and 1200 °C (S3 sample) annealing) were investigated for their gas-sensing properties towards inorganic gas like ammonia and VOCs like acetone, and isopropyl alcohol. Remarkably, annealing at 1200 °C yielded S3 sample with higher response (7.5 %) towards ammonia at room temperature for 500 ppm concentration. This superior performance is attributed to increased surface area, narrowed bandgap, and faster response/recovery times (18/15 s) compared to other samples. The proposed sensing mechanism involves the adsorption and desorption of oxygen molecules on the sensor surface, altering refractive index and light scattering, ultimately modulating the transmitted light intensity. X-ray diffraction, SEM imaging, and UV–Vis absorption techniques confirmed the structure and morphology of the nanocomposites.

Acute occupational inhalation injuries-United States, 2011-2022.

Inhalation injuries due to acute occupational exposures to chemicals are preventable. National surveillance of acute inhalation exposures is limited. This study identified the most common acute inhalation exposure-related incidents by industry sector among US workers. To characterize inhalation-related injuries and their exposures during April 2011-March 2022, state and federal records from the Occupational Safety and Health Administration (OSHA) Occupational Safety and Health Information System (OIS) accident database were analyzed. Industry-specific injury, hospitalization, and fatality rates were calculated. The most frequent acute inhalation incidents investigated by OSHA were caused by inorganic gases (52.9%) such as carbon monoxide (CO) or acids, bases, and oxidizing chemical agents (12.9%) such as anhydrous ammonia. The largest number of fatal and nonfatal injuries were reported in the manufacturing (28.6%) and construction (17.2%) sectors. Workers were affected by acute inhalation exposures in most industries. Using this surveillance, employers can recognize frequently-occurring preventable acute inhalation exposures by industry, such as inorganic gases in the manufacturing sector, and implement prevention measures. Training of workers on exposure characteristics and limits, adverse health effects, and use of protective equipment by exposure agent can prevent inhalation injuries.

A sensitive CsBr/Cs3Bi2Br3I6 heterostructure perovskite gas sensor for H2S detection at room temperature with high stability

In this paper, a new all inorganic lead-free perovskite gas sensor based on CsBr/Cs3Bi2Br3I6 composite was prepared to detect low concentrations H2S gas at room temperature (23 ℃). A two-step method of evaporation and subsequent spraying process was adopted, which makes the vertical growing Cs3Bi2Br3I6 nanoplates uniformly coating on the surface of the CsBr microspheres and forming a heterogeneous structure based conductive path way. The gas sensing test results indicate that the sensor shows good selectivity and reliable repeatability for H2S detection with long-term stability over 60 days, and the lowest concentration detected is 0.5 ppm. The sensor shows satisfactory stability in the range of relative humidity from 44 to 83 %. The in-situ diffuse reflectance infrared Fourier transformations spectroscopy (DRIFTs) results confirm the formation and enhancement process of SO asymmetric telescopic vibration peak due to the introduction of H2S gas, supporting the synergistic mechanism of adsorption-desorption and dynamic defect passivation.

Potential environmental and human health menace of spent graphite in lithium-ion batteries

The growing demand for lithium-ion batteries for portable electronics and electric vehicles results in a booming lithium battery market, leading to a concomitant increase in spent graphite. This research investigated the potential impacts of spent graphite on environmental and human health using standardized toxicity extraction and Life Cycle Impact Assessment models. The spent graphite samples were classified as hazardous waste due to the average nickel content of 337.14 mg/L according to Chinese regulations. Besides, cadmium and fluorine were the other elements that exceeded the regulations threshold. Easily ignored aluminum and heavy metal cobalt are other harmful elements according to the results of Life Cycle Impact Assessments. All the metallic harmful elements mainly exist in a transferable state. Thermogravimetry infrared spectrometry coupled with mass spectrometry was employed to recognize the emitted gases and explore gas emission behavior. Inorganic gases of CO, H2S, SO2, SO3, oxynitride, HCl, and fluoride-containing gases were detected. Sulfur-containing gases released from spent graphite were contributed by the residual sulfuric acid after leaching. The correlation between the evolution of emitted gases and the heating schedule was established simultaneously. The research comprehensively illustrates the pollution of spent graphite and provides assistance for the design of green recycling schemes for spent graphite.

Emission inventory of inorganic trace gases from solid residential fuels over the National Capital Territory of India.

In developing nations, solid residential fuels are the major sources of primary energy for various domestic activities. To date, the emission inventory of inorganic trace gases over National Capital Territory (NCT) was prepared using either default or country-specific emission factors. In this paper, we report (for the first time) the spatial variation of emission factors (EFs) of inorganic trace gases (SO2, NO, NO2, CO, CO2, and CH4) from the residential fuels used in slums and rural areas of NCT determined using dilution chamber in the laboratory. 147 residential fuel samples, including fuelwood, dung cake, crop residues, coal, etc., were collected at 149 NCT locations out of 675 slum clusters and 146 rural villages. The range of EF(s) of SO2 (0.02 ± 0.01 to 0.04 ± 0.01gkg-1), CH4 (0.10 to 0.34gkg-1), NO2 (0.01 to 0.02gkg-1) is lower than the CO (3.55 ± 1.72 to 6.07 ± 1.53gkg-1) and CO2 (0 to 129.45 ± 46.94gkg-1). The north and north west districts of NCT are emission hotspots for CH4, NO, and NO2 emissions, whereas, the southern and northern areas of NCT are for CO2. These citywide emission inventories (0.05° × 0.05°) of inorganic trace gases are prepared using laboratory-determined EFs and available consumption data determined by recent survey information. Among solid residential fuels, fuel wood, and dung cake are two major contributors to inorganic trace gases in NCT.

Co-pyrolysis of Hami coal and mixed plastic: An interaction between primary volatiles study via in-situ Py-TOF-MS

Online detection of pyrolysis volatiles is essential for exploring the mechanism of coal and plastics co-pyrolysis. In-situ pyrolysis time-of-flight mass spectrometry (Py-TOF-MS) equipped with double ionization sources, vacuum ultraviolet photoionization (VUVPI) and electron ionization (EI), was used to analyze the release of primary volatiles during the pyrolysis and co-pyrolysis of Hami coal (HM) with mixed plastic (PP/LDPE and PP/LDPE/PS, with ratios of 3:2 and 12:8:1, respectively). Meanwhile, the interaction mechanism was discussed at the molecular level. According to the thermogravimetric (TG) results and the total ion currents (TIC) of primary volatiles with temperature, the inclusion of plastic shortens the overall reaction time. In-situ Py-TOF-MS results indicate that the volatiles produced from HM pyrolysis at lower temperatures induce the decomposition of PP and promote further dehydrogenation of long-chain C–C. Besides, the addition of PP visibly facilitates the transportation of hydrogen, which reacts with phenoxy from HM pyrolysis to produce diphenol. The further addition of LDPE after PP enhances the inhibitory effect of molten plastic on HM pyrolysis, resulting in a decrease in the content of diphenol, such as benzenediol (from 1.34% to 0.71%), methyl-benzenediol (from 1.12% to 0.68%) and dimethyl benzenediol/ethyl benzenediol (from 0.68% to 0.50%). The co-pyrolysis of HM with PP/LDPE/PS generates more aromatic products compared to that of theoretical value, such as styrene (from 0.29% to 3.16%), 1-ethenyl-3-methyl benzene (from 0.07% to 0.31%) and 1-butene-2,4-diphenyl (from 0.19% to 0.65%). This indicates that co-pyrolysis strengthens the breakage of Car-Cβ bond in the PS backbone. The addition of PS to the mixture plastic also promotes intramolecular and intermolecular hydrogen transfer in the system. For the evolution of inorganic gases, the addition of mixed plastics promotes the decomposition of aliphatic and aromatic carboxylic acids in coal at lower temperatures, resulting in a decrease in CO2.

Maternal Exposure to Arsenic and Its Impact on Maternal and Fetal Health: A Review.

Arsenic exposure is a significant public health issue, with harmful effects caused by its use in commercial products such as car batteries, pesticides, and herbicides. Arsenic has three main compounds: inorganic, organic, and arsine gas. Inorganic arsenic compounds in water are highly toxic. The daily intake of arsenic from food and beverages is between 20 and 300 mcg/day. Arsenic is known for its carcinogenic properties and is classified as a human carcinogen by different institutions. Exposure can lead to oxidative stress, DNA damage, and epigenetic deregulation, which can cause endocrine disorders, altered signal transduction pathways, and cell proliferation. In addition, arsenic can easily cross the placenta, making it a critical concern for maternal and fetal health. Exposure can lead to complications such as gestational diabetes, anemia, low birth weight, miscarriage, and congenital anomalies. Female babies are particularly vulnerable to the negative impact of arsenic exposure, with a higher risk of low weight for gestational age and congenital cardiac anomalies. Therefore, it is crucial to monitor and regulate the levels of arsenic in drinking water and food sources to prevent these adverse health outcomes. Further research is necessary to fully understand the impact of arsenic exposure on human health, especially during pregnancy and infancy, by implementing preventative measures and monitoring the levels of arsenic in the environment.

Instant‐in‐Air Liquid Metal Printed Ultrathin Tin Oxide for High‐Performance Ammonia Sensors

AbstractLiquid metal‐based printing techniques are emerging as an exemplary platform for harvesting non‐layered 2D materials with a thickness down to a few nanometres, leading to an ultra‐large surface‐area‐to‐volume ratio that is ideal for sensing applications. In this work, the synthesis of 2D tin dioxide (SnO2) by exfoliating the surface oxide of molten tin is reported which highlights the enhanced sensing capability of the obtained materials to ammonia (NH3) gas is reported. It is demonstrated that amperometric gas sensors based on liquid metal‐derived 2D SnO2 nanosheets can achieve excellent NH3 sensing performance at low temperature (150 °C) with and without UV light assistance. Detection over a wide range of NH3 concentrations (5–500 ppm) is observed, revealing a limit of detection at the parts per billion (ppb) level. The 2D SnO2 nanosheets also feature excellent cross‐interference performance toward different organic and inorganic gas species, showcasing a high selectivity. Further, ab initio DFT calculations reveal the NH3 adsorption mechanism is dominated by chemisorption with a charge transfer into 2D SnO2 nanosheets. In addition, a proof of concept for prototype flexible ammonia sensors is demonstrated by depositing 2D SnO2 on a polyimide substrate, signifying the high potential of employing liquid metal printed SnO2 for realizing wearable gas sensors.

Nanoplasmonic Au:CuO thin films functionalized with APTES to enhance the sensitivity of gas sensors

Carbon monoxide (CO) is a highly flammable and toxic gas to humans and animals, that’s why its detection and monitoring are crucial. A promising technique to develop a robust and cheap gas sensor, operating at room temperature, is Localized Surface Plasmon Resonance (LSPR) sensing. However, LSPR sensing of inorganic gas molecules, such as CO, is challenging due to their extremely small differences in refractive indices. In this work, a nanoplasmonic thin film, composed of Au NPs semi-embedded in a CuO matrix (Au:CuO) was functionalized with a silane self-assembled monolayer (APTES molecule) that enhanced the sensitivity of the film to a mixture of CO (50 ppm) in Argon. Three different concentrations of APTES (0.1 %, 1.0 %, and 5.0 %) were silanized on Au:CuO thin film surface, and all the functionalized Au:CuO thin films showed better sensing results than bare Au:CuO thin film. The functionalized Au:CuO thin film with 0.1 % of APTES revealed the best sensing characteristics. Its sensitivity was almost 3 times higher than that of the unmodified Au:CuO thin film. Au:CuO thin films functionalized with APTES are potentially relevant to developing sensitive and selective LSPR sensors for the detection of inorganic gases such as CO, in harsh environments.

Studying the Adsorption of Gas Molecules and Defects on Modulating the Electronic Transport Characteristics of Monolayer Penta-BN2-Based Devices.

Two-dimensional atomic layer materials, as an important part of the post-Moore era, have recently become an ideal choice for the preparation of high-efficiency, low-power, and miniaturized gas sensors. In this work, our study utilized density functional theory and the nonequilibrium Green's function method to investigate the electronic properties of the pentagonal BN2 (P-BN2) monolayer, as well as its gas-sensing properties for organic and inorganic gases. We also investigated how defects affect the quantum transport properties of the P-BN2-based device. Our findings demonstrate that the CO, H2S, NH3, SO2, C2H5OH, C3H6OH, CH3OH, and CH4 undergo physisorption on the P-BN2 monolayer, while NO, NO2, C2H2, C2H4, and HCHO undergo chemisorption. Then, we analyzed the impact of gas molecules chemisorbed on the P-BN2 monolayer on the electronic transport properties of the P-BN2-based gas sensor. When these five gas molecules are adsorbed, the current of the P-BN2-based gas sensor is greatly reduced. In addition, the effect of defects on the quantum transport properties of the P-BN2-based device is investigated. The results indicate that defects of N, B, and BN atoms lead to a decrease in the current of P-BN2-based nanodevices. Moreover, both the adsorption of gas molecules and the formation of vacancy defects leading to a decrease in device current can be revealed by the local device density of states near the zero-bias Fermi level, elucidating their microscopic mechanisms. Finally, gas molecules can also cause a decrease in the current of defect systems. These theoretical studies are of great significance for exploring two-dimensional atomic layer materials as high-efficiency gas sensors.

Bioinspired supramolecular arrayed heterojunction-based room-temperature sensor for high-performance gas detection

Nitrogen dioxide (NO2) has been severely polluting the atmosphere and deteriorating human beings’ sustainable lives. Therefore, development of gas sensors for high-selectivity and high-sensitivity detection of NO2 has been attracting increasing attention. The state-of-the-art inorganic NO2 gas sensors require harsh fabrication conditions or toxic materials, making the devices intrinsically eco-unfriendly. Furthermore, in most cases the sensors work at high temperatures. These disadvantages severely impede their practical applications. Herein, we report a room-temperature and highly-integrated NO2 sensor composed of p-type self-assembled peptide fibrillar nanoforests (SPNFs) scaffolded with n-type SnO2 nanoparticles (NPs) heterojunctions. The p-n conformations provide efficient access to target gases and allow reliable electron transformations, while the SPNFs afford a large specific surface area and multiporous structures for gas adsorption and SnO2 NPs dispersion, resulting in an ultrahigh selectivity for NO2 detection. Especially, the sensing performance can be optimized by modulating the thickness and density of the SPNFs, showing a high response, short response and recovery times, along with a low detection limitation. Our strategy demonstrates the development of a bioinspired platform by utilizing peptide self-assemblies to fabricate integrated sensors for polluting gas detections.

Switchable operating modes enable low power consumption and improved gas sensing efficiency in MoS2/BP heterojunction

Low power consumption and reliable response are two main requirements for gas sensors to be suitable for emerging Internet of Things and Industrial Internet applications. However, state-of-the-art inorganic chemiresistor-type gas sensors have difficulty overcoming the limitations of high-power consumption. Integrating complementary photovoltaic effect and gas sensing functions in a single heterojunction is an alternative approach. Herein, we present diode-type gas sensors based on two-dimensional heterojunction, which can switch the operating modes by adjusting the bias voltage or illumination condition. At forward bias, the sensor has a high response of 310 and good selectivity, while in self-powered mode, it exhibits an open circuit voltage of 0.36 V, a fast recovery rate (27.3 s), and low power consumption (20 nW). Furthermore, the gas sensing mechanism at room temperature was confirmed by energy potential, photoluminescence, Raman spectra measurements, and the DFT calculations before and after NO2 exposure, indicating that the electron transfer between the heterojunction and NO2 molecules was the dominant factor. The proposed gas sensor with the switchable operating modes may open new avenues for the development of advanced energy-efficient, high-efficiency gas sensing devices, and concepts.

Characterizing and modeling hydrogen sulfide production in anaerobic digestion of livestock manure, agro‐industrial wastes, and wastewater sludge

AbstractHydrogen sulfide (H2S) is the most undesirable inorganic gas in biogas from anaerobic digestion (AD). However, H2S production in AD is complex and understanding of its processes is still limited. This study performed six controlled batch anaerobic co‐digestion experiments to investigate H2S production. Materials were obtained from four field anaerobic digester systems and co‐digestion feedstocks from agroindustry. An additional precipitation experiment was conducted to further examine H2S production dynamics. Digesters containing highly soluble, carbohydrate‐based wastes had a high H2S final specific production (FSP) value. Additionally, the FSP values were negatively correlated with the initial Fe(II):S ratios in the digester liquid of the batch tests. The precipitation experiment indicated that iron sulfide precipitation was preferred in the presence of an anaerobic community. The H2S production as a time series was successfully modeled using a generalized additive model (R2 > 0.82). This study revealed that sulfate, phosphorus, and iron concentrations are important predictors and potential inhibitors of H2S production in AD. Further examination of real‐time H2S modeling in AD is warranted.

Mechanism investigations on co-pyrolysis of polyethylene and biomass using ReaxFF simulation and DFT computation

Co-pyrolysis of plastics and biomass is a promising solution for waste management and renewable energy utilization. There is still no consensus on the distributions of co-pyrolysis products and the reaction mechanisms between the polyethylene (PE) plastics and biomass components at the molecular level. In this work, the product distribution, co-pyrolysis mechanism, and electronic characteristic of PE and major biomass components such as cellulose (CE), hemicellulose (HC), and lignin (LG) were investigated at the atomistic level using reactive force field simulation and density functional theory computation. The co-pyrolysis of PE and biomass facilitates the release of non-carbon radicals, which enhances the reactivity of macromolecular fractions to high-quality oils. HC promotes the char degradation and oxygenated oil retention, whereas CE accelerates the decomposition of oxygen-free char to light hydrocarbons and inorganic gases. LG inhibits the conversion of oxygenated oil to CO/CO2 and retards the secondary cracking of oxygen-free oil. Alkyne is mostly generated from α-O-4 LG dimer, whereas olefin is mainly derived from γ-O-4 LG dimer. β-O-4 LG dimer accelerates the conversion of char to oil, while it decreases gas emissions. The electronic characteristics such as the Fukui function, frontier orbitals, and total electron density demonstrate the reaction sites of biomass monomers. For CE and HC, the hydroxyl groups on methylene are the nucleophilic sites, and the O atoms of hydroxyl on the pyran ring are prone to the electrophilic attack by PE. Except for O atoms in LG dimers, the unsubstituted C atoms on the benzene ring are inclined to the nucleophilic sites, whereas the C and para-C atoms located at hydroxyl and methoxy are susceptible to the electrophilic attack by PE. This work elucidates the differences in the co-pyrolysis reaction characteristics of various biomass structures, which provides scientific and theoretical guidance for the efficient resource exploitation of biomass and waste plastics.

Polymeric interfacial engineering approach to perovskite-functionalized organic transistor-type gas sensors

Organic semiconductors (OSCs) are promising sensing materials for printed organic gas sensors. Although OSCs show promise since they are mechanically flexible, cost-effective, and lightweight, they still face challenges related to low sensitivity and poor stability under ambient conditions; their development therefore lags that of inorganic-based gas sensors. Functional nanomaterials can be incorporated into organic semiconductors to complement the gas sensitivity and stability. Herein, we describe the fabrication of novel organic–inorganic hybrid gas sensors via the blending of perovskite nanocrystals and conductive polymer. We introduced a perovskite-structured material, CsPbBr3, into a conductive polymer matrix, which substantially improved its gas-sensing performance while maintaining its high responsivity and response rates. To further improve the adsorption of target gas molecules, we modified the surface of the perovskite using a zwitterionic polymer subjected to a hydration treatment. The results demonstrate that the amide group of the encapsulation polymer exhibits high affinity toward NO2 gas molecules and that this affinity becomes more pronounced upon hydration of the polymer. We also demonstrate the perovskite materials in the semiconducting polymer layer can protect the polymer thin film against oxidation during prolonged storage under ambient conditions because of the perovskite crystals’ ability to adsorb oxidizing molecules.

Key Problems and Countermeasures in CO2 Flooding and Storage

AbstractBased on literature research in combination with the practice of CO2 flooding and storage in Jilin Oilfield, this study assesses the key problems in CO2 flooding and storage, proposing the corresponding countermeasures from five aspects of CO2 gas source condition, namely geological condition evaluation, scheme design incoordination with other production methods, economic and effectiveness evaluation, together with dynamic monitoring and safety evaluation. The results show that CO2 flooding is the most economic and effective CO2 storage method. In eastern China, inorganic origin CO2 gas reservoirs are widely developed and are especially the most enriched in the Paleozoic carbonate rock strata and the Cenozoic Paleogene–Neogene system, which provide a rich resource base for CO2 flooding and storage. In the future, CO2 generated in the industrial field will become the main gas source of CO2 flooding and storage. The evaluation of geological conditions of oil and gas reservoirs is the basis for the potential evaluation, planning scheme design and implementation of CO2 flooding and storage. CO2 storage should be below the depth of 800 m, the CO2 flooding and storage effects in low‐permeability oil reservoirs being the best. CO2 geological storage mechanisms primarily consist of tectonic geological storage, bound gas storage, dissolution storage, mineralization storage, hydrodynamic storage and coalbed adsorption storage. The practice of CO2 flooding and storage in Jilin Oilfield demonstratesthat the oil increment by CO2 flooding is at least 24% higher than by conventional water flooding. The most critical factor determining the success or failure of CO2 flooding and storage is economic effectiveness, which needs to be explored from two aspects: the method and technology innovation along with the carbon peaking and carbon neutrality policy support. After CO2 is injected into the reservoir, it will react with the reservoir and fluid, the problem of CO2 recovery or overflow will occur, so the dynamic monitoring and safety evaluation of CO2 flooding and storage are very important. This study is of great significance to the expansion of the application scope of CO2 flooding and storage and future scientific planning and deployment.

Mineralogy and phase transition mechanisms of atmospheric mineral particles: Migration paths, sources, and volatile organic compounds

Inorganic mineral particles play an important role in the formation of atmospheric aerosols in the Sichuan Basin. Atmospheric haze formation is accompanied by the phase transition of mineral particles under high humidity and stable climatic conditions. Backward trajectory analysis was used in this study to determine the migration trajectory of atmospheric mineral particles. Furthermore, Positive matrix factorization (PMF) was used to analyze the sources of atmospheric mineral particles. The phase transition mechanisms of atmospheric mineral particles were studied using ion chromatography, inductively coupled plasma emission spectrometry, total organic carbon analysis, X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscopy coupled with energy dispersive spectrometry, and grand canonical Monte Carlo methods. Three migration and phase transition paths were identified for the mineral particles. Sources of atmospheric mineral particles included combustion, vehicle emissions, industrial emissions, agricultural sources, and mineral dust. The main mineral phases in atmospheric particles, calcite and dolomite, were transformed into gypsum, and muscovite may be transformed into kaolinite. The phase transition of mineral particles seriously affects the formation of aerosols and worsens haze. Typically, along the Nanchong-Suining-Neijiang-Zigong-Yibin path, calcite is converted into gypsum under the influence of man-made inorganic pollution gases, which worsen the haze conditions and cause slight air pollution for 3–5 days. However, along the Guangyuan-Mianyang-Deyang-Chengdu-Meishan-Ya'an path, anthropogenic volatile organic compounds (VOCs) hindered gypsum formation from dolomite. Furthermore, dolomite and VOCs formed stable adsorption systems (system energies from −0.41 to −4.76 eV, long bonds from 0.20 to 0.24 nm). The adsorption system of dolomite and m/p-xylene, with low system energy (−1.46 eV/−1.33 eV) and significant correlation (r2 = 0.991, p < 0.01), was the main cause of haze formation. Consequently, calcite gypsification and dolomite–-VOC synergism exacerbated regional haze conditions. This study provides a theoretical reference for the mechanism of aerosol formation in basin climates.

A review of environmental emissions from asphalt plants and paving

Asphalt is a black, thermoplastic, hydrocarbon material extracted from crude oil and widely used in road construction all over the world. In order to meet the requirements of construction technology, asphalt always needs to be heated to flow state in the process of mixing and paving, during which a large amount of asphalt fume is released. Asphalt fume is a complex mixture of inorganic compound gases, volatile organic compounds and particulate matter, which poses a serious threat to the natural environment and the health of practitioners. This review presents HMA and WMA constituents and the potential health effects of criteria and Hazardous pollutants generated from asphalt pavement construction. Hot mix asphalt (HMA) and warm mix asphalt (WMA)are a major construction materials used for highway roads, building roads, airport runways, parking, and other pavement repairs in the worldwide. During HMA construction, a considerable number of volatile organic compounds (VOCs) are generated during asphalt pavement construction, and present negative effects on workers health. Accurate identification, quantification and measurement of emissions during HMA and WMA paving operations were used to identify and quantify VOCs, SVOCs, hazardous air pollutants (HAPs) and polycyclic aromatic hydrocarbons (PAHs) in asphalt fumes during production and paving activities.

Three-dimensional ordered DNA network constructed by a biomarker pair for accurate monitoring of colorectal cancer

Precise and early screening of colorectal cancer (CRC) is one crucial yet challenging task for its treatment, and the analysis of multi-targets of CRC in a single assay with high accuracy is essential for pathological research and clinical diagnosis. Here, a CRC-related biomarker pair, microRNA-211 (miRNA-211) and H2S, was detected by constructing a three-dimensional (3D) ordered DNA network. First, trace amount of miRNA-211 could initiate a hybridization chain reaction-based amplification process. A highly ordered 3D DNA network was formed based on the organized assembly of DNA-cube frameworks that were constructed by DNA origamis and Ag nanoparticles (NPs) encapsulated inside. In the presence of the H2S, Ag NPs within the network can be etched to generate Ag2S quantum dots, which could be better visualized in fluorescence in situ cell imaging. Using the 3D DNA ordered network as the sensing platform, it can acquire dual analysis of biomolecule (miRNA-211) and inorganic gas (H2S) in vitro, overcoming the limitations of single type of biomarker detection in a single assay. This assay achieved a wide linearity range of H2S from 0.05 to 10 μM, and exhibited a low limit of detection of 4.78 nM. This strategy allows us to acquire the spatial distributions of H2S and miRNA expression levels in living CRC cells simultaneously, providing a highly sensitive and selective tool for early screening and monitoring of CRC.

Abraham Solvation Parameter Model: Revised Predictive Expressions for Solute Transfer into Polydimethylsiloxane Based on Much Larger and Chemically Diverse Datasets

Updated Abraham model correlations are reported for the transfer of organic solutes and inorganic gases to a polydimethylsiloxane coating from both water and the gas phase based on published experimental data for more than 220 different compounds. The derived mathematical expressions back-calculate the observed partitioning behavior to within standard deviations of the residuals of 0.206 and 0.176 log units, respectively.