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Pressure-induced phase transformations (PTs) in Si, the most important electronic material, have been broadly studied, whereas strain-induced PTs have never been studied in situ. Here, we reveal in situ various important plastic strain-induced PT phenomena. A correlation between the direct and inverse Hall-Petch effect of particle size on yield strength and pressure for strain-induced PT is predicted theoretically and confirmed experimentally for Si-IâSi-II PT. For 100 nm particles, the strain-induced PT Si-IâSi-II initiates at 0.3 GPa under both compression and shear while it starts at 16.2 GPa under hydrostatic conditions. The Si-IâSi-III PT starts at 0.6 GPa but does not occur under hydrostatic pressure. Pressure in small Si-II and Si-III regions of micron and 100 nm particles is â¼5-7 GPa higher than in Si-I. For 100 nm Si, a sequence of Si-I â I + II â I + II + III PT is observed, and the coexistence of four phases, Si-I, II, III, and XI, is found under torsion. Retaining Si-II and single-phase Si-III at ambient pressure and obtaining reverse Si-IIâSi-I PT demonstrates the possibilities of manipulating different synthetic paths. The obtained results corroborate the elaborated dislocation pileup-based mechanism and have numerous applications for developing economic defect-induced synthesis of nanostructured materials, surface treatment (polishing, turning, etc.), and friction.
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In situ studies under severe plastic deformation at high pressures, employing shear diamond anvil cells, have recently gained much interest in the high-pressure community owing to their potential applications in material processing methods, mechanochemistry, and geophysics. These studies, combined with multi-scale computational simulations, provide important insights into the transient hierarchical microstructural evolution, structural phase transitions, and orientation relationship between parent and daughter phases and help establish the kinetics of strain-induced phase transitions under severe plastic deformation. The existing SDACs are mostly used in axial x-ray diffraction geometry due to geometrical constraints providing less reliable information about stress states and texture. Their asymmetric design also poses serious limitations to high-pressure shear studies on single crystals. To overcome these limitations, a new compact symmetric shear diamond anvil cell has been designed and developed for in situ high-pressure torsion studies on materials. The symmetric angular opening and short working distance in this new design help obtain a more reliable crystallographic orientation distribution function and lattice strain states up to a large Q range. Here, we present the advantages of the symmetric design with a few demonstrative studies.
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The protection of Earth's stratospheric ozone (O3) is an ongoing process under the auspices of the universally ratified Montreal Protocol and its Amendments and adjustments. A critical part of this process is the assessment of the environmental issues related to changes in O3. The United Nations Environment Programme's Environmental Effects Assessment Panel provides annual scientific evaluations of some of the key issues arising in the recent collective knowledge base. This current update includes a comprehensive assessment of the incidence rates of skin cancer, cataract and other skin and eye diseases observed worldwide; the effects of UV radiation on tropospheric oxidants, and air and water quality; trends in breakdown products of fluorinated chemicals and recent information of their toxicity; and recent technological innovations of building materials for greater resistance to UV radiation. These issues span a wide range of topics, including both harmful and beneficial effects of exposure to UV radiation, and complex interactions with climate change. While the Montreal Protocol has succeeded in preventing large reductions in stratospheric O3, future changes may occur due to a number of natural and anthropogenic factors. Thus, frequent assessments of potential environmental impacts are essential to ensure that policies remain based on the best available scientific knowledge.
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Ozono Estratosférico , Rayos Ultravioleta , Humanos , Ozono Estratosférico/análisis , Rayos Ultravioleta/efectos adversos , Ozono/química , Cambio ClimáticoRESUMEN
Stream flow forecasting is a crucial aspect of hydrology and water resource management. This study explores stream flow forecasting using two distinct models: the Soil and Water Assessment Tool (SWAT) and a hybrid M5P model tree. The research specifically targets the daily stream flow predictions at the MH Halli gauge stations, located along the Hemvati River in Karnataka, India. A 14-year dataset spanning from 2003 to 2017 is divided into two subsets for model calibration and validation. The SWAT model's performance is evaluated by comparing its predictions to observed stream flow data. Residual time series values resulting from this comparison are then resolved using the M5P model tree. The findings reveal that the hybrid M5P tree model surpasses the SWAT model in terms of various evaluation metrics, including root-mean-square error, coefficient of determination (R2), Nash-Sutcliffe efficiency, and degree of agreement (d) for the MH Halli stations. In conclusion, this study shows the effectiveness of the hybrid M5P tree model in stream flow forecasting. The research contributes valuable insights into improved water resource management and underscores the importance of selecting appropriate models based on their performance and suitability for specific hydrological forecasting tasks.
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Modelos Teóricos , Lluvia , India , Ríos , Movimientos del Agua , Hidrología , Monitoreo del Ambiente/métodos , PredicciónRESUMEN
Various phenomena (phase transformations (PTs), chemical reactions, microstructure evolution, strength, and friction) under high pressures in diamond-anvil cell are strongly affected by fields of stress and plastic strain tensors. However, they could not be measured. Here, we suggest coupled experimental-analytical-computational approaches utilizing synchrotron X-ray diffraction, to solve an inverse problem and find fields of all components of stress and plastic strain tensors and friction rules before, during, and after α-ω PT in strongly plastically predeformed Zr. Results are in good correspondence with each other and experiments. Due to advanced characterization, the minimum pressure for the strain-induced α-ω PT is changed from 1.36 to 2.7 GPa. It is independent of the plastic strain before PT and compression-shear path. The theoretically predicted plastic strain-controlled kinetic equation is verified and quantified. Obtained results open opportunities for developing quantitative high-pressure/stress science, including mechanochemistry, synthesis of new nanostructured materials, geophysics, astrogeology, and tribology.
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Cowpea is known for its high protein content (18-25%) and also chiefly raised for green fodder. The infesting pests, pod borer and aphids are the most destructive ones. To control these pests, chlorantraniliprole emerges as a promising molecule. Thus, its needs to assess the dissipation nature of the chlorantraniliprole. Hence, a trial was conducted at IIVR, Varanasi, India. The residue analysis was done through solid phase extraction method followed by gas chromatoghraphy analysis. The analytical method was standardized and validated according to international standard. The half-life of chlorantraniliprole in cowpea pods was estimated in the range of 2.79- 2.33 days in the year-I and 2.51-2.32 days in the year-II for single dose (SD) and double dose (DD) respectively. Similarly, half-life of the chlorantraniliprole in leaves 2.43-2.27 days whereas, 1.94-1.70 days in case of soil. The exposure of the residues in pods were less than maximum permissible intake (MPI). The RQ values revealed that there could be negligible risk to earthworms and arthropods. Washing with boiling water was found the most effective decontamination treatment to remove residue from cowpea pods. Thus, it could be concluded that chlorantraniliprole does not pose any significant threat when uses in cowpea in a particular dose.
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Insecticidas , Residuos de Plaguicidas , Vigna , Cinética , Insecticidas/análisis , Descontaminación/métodos , Monitoreo del Ambiente , Semivida , Inocuidad de los Alimentos , Residuos de Plaguicidas/análisisRESUMEN
The deleterious effects of solar ultraviolet (UV) radiation on construction materials, especially wood and plastics, and the consequent impacts on their useful lifetimes, are well documented in scientific literature. Any future increase in solar UV radiation and ambient temperature due to climate change will therefore shorten service lifetimes of materials, which will require higher levels of stabilisation or other interventions to maintain their lifetimes at the present levels. The implementation of the Montreal Protocol and its amendments on substances that deplete the ozone layer, controls the solar UV-B radiation received on Earth. This current quadrennial assessment provides a comprehensive update on the deleterious effects of solar UV radiation on the durability of natural and synthetic materials, as well as recent innovations in better stabilising of materials against solar UV radiation-induced damage. Pertinent emerging technologies for wood and plastics used in construction, composite materials used in construction, textile fibres, comfort fabric, and photovoltaic materials, are addressed in detail. Also addressed are the trends in technology designed to increase sustainability via replacing toxic, unsustainable, legacy additives with 'greener' benign substitutes that may indirectly affect the UV stability of the redesigned materials. An emerging class of efficient photostabilisers are the nanoscale particles that include oxide fillers and nanocarbons used in high-performance composites, which provide good UV stability to materials. They also allow the design of UV-shielding fabric materials with impressive UV protection factors. An emerging environmental issue related to the photodegradation of plastics is the generation of ubiquitous micro-scale particles from plastic litter exposed to solar UV radiation.
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Energía Solar , Rayos Ultravioleta , Ozono Estratosférico , Luz Solar , PlásticosRESUMEN
The Environmental Effects Assessment Panel of the Montreal Protocol under the United Nations Environment Programme evaluates effects on the environment and human health that arise from changes in the stratospheric ozone layer and concomitant variations in ultraviolet (UV) radiation at the Earth's surface. The current update is based on scientific advances that have accumulated since our last assessment (Photochem and Photobiol Sci 20(1):1-67, 2021). We also discuss how climate change affects stratospheric ozone depletion and ultraviolet radiation, and how stratospheric ozone depletion affects climate change. The resulting interlinking effects of stratospheric ozone depletion, UV radiation, and climate change are assessed in terms of air quality, carbon sinks, ecosystems, human health, and natural and synthetic materials. We further highlight potential impacts on the biosphere from extreme climate events that are occurring with increasing frequency as a consequence of climate change. These and other interactive effects are examined with respect to the benefits that the Montreal Protocol and its Amendments are providing to life on Earth by controlling the production of various substances that contribute to both stratospheric ozone depletion and climate change.
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Pérdida de Ozono , Ozono , Cambio Climático , Ecosistema , Humanos , Ozono/química , Ozono Estratosférico , Rayos UltravioletaRESUMEN
Prolonged inorganic arsenic (iAs) exposure is widely associated with brain damage particularly in the hippocampus via oxidative and apoptotic pathways. Resveratrol (RES) has gained considerable attention because of its benefits to human health. However, its neuroprotective potential against iAs-induced toxicity in CA1 region of hippocampus remains unexplored. Therefore, we investigated the neuroprotective efficacy of RES against arsenic trioxide (As2O3)-induced adverse effects on neuronal morphology, apoptotic markers and oxidative stress parameters in mouse CA1 region (hippocampus). Adult female Swiss albino mice of reproductive maturity were orally exposed to either As2O3 (2 and 4 mg/kg bw) alone or in combination with RES (40 mg/kg bw) for a period of 45 days. After animal sacrifice on day 46, the perfusion fixed brain samples were used for the observation of neuronal morphology and studying the morphometric features. While the freshly dissected hippocampi were processed for biochemical estimation of oxidative stress markers and western blotting of apoptosis-associated proteins. Chronic iAs exposure led to significant decrease in Stratum Pyramidale layer thickness along with reduction in cell density and area of Pyramidal neurons in contrast to the controls. Biochemical analysis showed reduced hippocampal GSH content but no change in total nitrite (NO) levels following iAs exposure. Western blotting showed apparent changes in the expression levels of Bax and Bcl-2 proteins following iAs exposure, however the change was statistically insignificant. Contrastingly, iAs +RES co-treatment exhibited substantial reversal in morphological and biochemical observations. Together, these findings provide preliminary evidence of neuroprotective role of RES on structural and biochemical alterations pertaining to mouse hippocampus following chronic iAs exposure.
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Trióxido de Arsénico/toxicidad , Lesiones Encefálicas , Hipocampo , Células Piramidales , Resveratrol/farmacología , Animales , Arsénico/toxicidad , Lesiones Encefálicas/inducido químicamente , Lesiones Encefálicas/metabolismo , Lesiones Encefálicas/patología , Lesiones Encefálicas/prevención & control , Femenino , Hipocampo/lesiones , Hipocampo/metabolismo , Hipocampo/patología , Ratones , Células Piramidales/metabolismo , Células Piramidales/patologíaRESUMEN
This assessment by the Environmental Effects Assessment Panel (EEAP) of the United Nations Environment Programme (UNEP) provides the latest scientific update since our most recent comprehensive assessment (Photochemical and Photobiological Sciences, 2019, 18, 595-828). The interactive effects between the stratospheric ozone layer, solar ultraviolet (UV) radiation, and climate change are presented within the framework of the Montreal Protocol and the United Nations Sustainable Development Goals. We address how these global environmental changes affect the atmosphere and air quality; human health; terrestrial and aquatic ecosystems; biogeochemical cycles; and materials used in outdoor construction, solar energy technologies, and fabrics. In many cases, there is a growing influence from changes in seasonality and extreme events due to climate change. Additionally, we assess the transmission and environmental effects of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which is responsible for the COVID-19 pandemic, in the context of linkages with solar UV radiation and the Montreal Protocol.
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The shoot and fruit borer, Earias vittella Fab. (Lepidoptera: Nolidae) is an important and most devastating insect pest on okra and cotton. The pest mainly responsible for causing significant direct damage to tender shoots and fruits of okra, flowers and green bolls of cotton causing net yield loss in both crops. Many non-chemical control strategies have been developed under the insect pest management program, A complete knowledge on the antennal morphology of E. vitella is essential for future electrophysiological and behavioural studies. In the present study, the antennal morphology and types of sensilla on the antennae of both sexes of E. vitella were examined using light and scanning electron microscopy. Nine distinct types of sensilla were identified on the antennae of both sexes: sensilla trichodea, sensilla basiconica, sensilla coeloconica, sensilla auricillica (multiporous), sensilla chaetica, uniporous peg sensilla (uniporous), sensilla styloconica, sensilla squamiformia and bohm bristles (aporous). Among all sensilla, the most widespread are multiporous sensilla trichodea with 42.90 ± 1.77/flagellomere in male and 37.38 ± 1.38/flagellomere in female. Sensilla basiconica were the second most common sensillum type in male antennae with 15.67 ± 1.92/flagellomere. Other multiporous sensilla such as auricillica (11.90 ± 0.99) and coeloconica (4.57 ± 0.25) were significantly more abundant in female than in male antennae. Results of the study provide morphological evidence that E. vitella antennae possess microscopic cuticular structures that can play a role in perception of pheromones, plant odours and other chemical stimulants. This will open up opportunities to assess the possibility of using pheromones and plant-derived compounds for the monitoring or management of E. vittella moths in the agricultural landscapes.
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Mariposas Nocturnas/anatomía & histología , Sensilos/anatomía & histología , Animales , Femenino , Masculino , Microscopía Electrónica de Rastreo/métodos , Microscopía Electrónica de Transmisión/métodos , Mariposas Nocturnas/metabolismo , Feromonas , Sensilos/ultraestructuraRESUMEN
This assessment, by the United Nations Environment Programme (UNEP) Environmental Effects Assessment Panel (EEAP), one of three Panels informing the Parties to the Montreal Protocol, provides an update, since our previous extensive assessment (Photochem. Photobiol. Sci., 2019, 18, 595-828), of recent findings of current and projected interactive environmental effects of ultraviolet (UV) radiation, stratospheric ozone, and climate change. These effects include those on human health, air quality, terrestrial and aquatic ecosystems, biogeochemical cycles, and materials used in construction and other services. The present update evaluates further evidence of the consequences of human activity on climate change that are altering the exposure of organisms and ecosystems to UV radiation. This in turn reveals the interactive effects of many climate change factors with UV radiation that have implications for the atmosphere, feedbacks, contaminant fate and transport, organismal responses, and many outdoor materials including plastics, wood, and fabrics. The universal ratification of the Montreal Protocol, signed by 197 countries, has led to the regulation and phase-out of chemicals that deplete the stratospheric ozone layer. Although this treaty has had unprecedented success in protecting the ozone layer, and hence all life on Earth from damaging UV radiation, it is also making a substantial contribution to reducing climate warming because many of the chemicals under this treaty are greenhouse gases.
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Cambio Climático , Ozono Estratosférico , Rayos Ultravioleta , Salud Ambiental , Humanos , Microplásticos , Naciones UnidasRESUMEN
Diisopropylammonium salts have drawn attention in recent years due to their room-temperature ferroelectric properties. Triclinic diisopropylammonium perchlorate (DIPAP) exhibits ferroelectricity at room temperature. We have carried out density functional theory calculations to assign the phonon modes in DIPAP. High-pressure Raman spectra of DIPAP are recorded up to â¼3 GPa. Discontinuity in the NH2 bending and stretching mode frequencies and the appearance of new bands at 0.7 GPa suggest a phase transition by a rearrangement in the hydrogen network. Broadening of lattice modes at 1.3-1.7 GPa indicates a loss of crystalline nature above 1.7 GPa. High-pressure synchrotron X-ray diffraction of DIPAP shows an isostructural phase transition at 0.6 GPa and confirms amorphization at 1.5 GPa that may lead to a loss of ferroelectricity above this pressure. The ambient phase becomes reversible after releasing the pressure. The bulk modulus of DIPAP is determined to be 16.5 GPa.
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A hydrothermal synthesis method was employed for the preparation of tin sulfide (α-SnS) microrod samples (SnS-A and SnS-B) using ethylenediamine and deionized water as the surfactant at ratios from 50 : 50 to 100 : 00. The atomic structures of the α-SnS microrods were studied using atomic pair distribution function (PDF) analysis and total synchrotron X-ray scattering data. The synchrotron X-ray diffraction (ScXRD) patterns and PDF data reveal that the structure of the SnS microrods is orthorhombic. From the refinement of the PDF, the first and second peaks correspond to nearest (Sn2+-S2-) and second nearest distances (Sn2+-Sn2+) of 2.546 (0.003) Å and 4.106 (0.004) Å, and 2.527 (0.005) Å and 4.087 (0.006) Å for SnS-A and SnS-B samples, respectively. The TEM results show that samples SnS-A and SnS-B have a microrod structure, with microrod diameters of 800 nm and 500 nm with lengths of tens of micrometers, respectively. The SnS-A and SnS-B samples show a direct band gap of 1.6 eV and 2 eV, respectively, using the Kubelka-Munk transformation of the UV-visible spectra. The micro-Raman spectra of the SnS-A and SnS-B microrods exhibited an Ag mode of SnS at 228.4 and 223 cm-1, respectively. The second peaks at 306.7, and 309 cm-1 are associated with the secondary phases of the SnS2 phase, whereas the third broad peaks at 616.5, and 613 cm-1 revealed that there was a deformation mode of sulfate in the SnS-A and SnS-B samples.
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Benzoic acid derivatives are important molecular systems in the pharmaceutical industry. Salicylic acid is distinct among the derivatives of benzoic acid due to the presence of an intramolecular hydrogen bond. With a view to study the evolution of inter and intramolecular hydrogen bonding at shorter length scales, in situ high pressure Raman spectroscopic measurements, angle dispersive X-ray diffraction experiments, and density functional theory (DFT) based first principle calculations have been carried out on crystalline salicylic acid. Subtle structural modifications are noted across â¼1 GPa leading to structural phase transition to a new crystalline phase above 7 GPa which is reversible. Substantial softening of the OH stretching Raman mode associated with intramolecular hydrogen bond is observed prior to the transition pressure. Possible molecular configurations associated with tautomerization are discussed with the aid of DFT calculations.
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Solar UV radiation adversely affects the properties of organic materials used in construction, such as plastics and wood. The outdoor service lifetimes of these materials are influenced by their rates of degradation under solar UV radiation as well as by other climate factors such as temperature, moisture, and atmospheric pollutants. While recovery of the stratospheric ozone layer is expected, local increases in UV radiation are still likely to occur, especially in the tropics, but also elsewhere because of climate change effects. Such increases, when taken together with an increased ambient temperature due to climate change, can significantly shorten the service lifetimes of organic building materials. Several proven technologies, including the use of UV stabilisers, surface treatments or coatings have been developed over the years to mitigate these adverse effects. While these technologies should be able to compensate for any realistic future UV radiation and climate change scenarios, they will also add significantly to the lifetime cost of material in relevant products. Shorter outdoor lifetime of the plastic components in photovoltaic (PV) modules is a serious concern in the solar energy industry. To ensure module durability over the full service-lifetime (of about â¼20 years) of the light-harvesting PV components, better stabilisation technologies are being investigated. The present trend towards more environmentally sustainable materials in building, and environmental impact of additives such as stabilisers, need to be considered in addition to their engineering performance. This may require the phasing out of some conventional additives used in plastics as well as substituting wood or other materials in place of plastics in buildings. Depending on the relative costs of mitigation, substituting more UV-stable materials for conventional ones in outdoor products may also be a viable option with some categories of products. Neither the global cost of mitigation of the effects of climate change on materials nor the long-term sustainability of the technologies available for the purpose, have been estimated. Plastic waste and litter exposed outdoors to solar UV radiation over extended periods undergo cracking and fragmentation into small pieces (of micro- and nano-scale size). Release of these fragments into the environment, particularly in the aquatic environment, poses a potential threat to marine biota. Already several hundred of species are known to ingest these fragments that can potentially accumulate additives and pollutants from water. This is a potential threat to humans because 25% of fish marketed for human consumption have been reported to contain microplastics in their digestive systems. The focus of this assessment is on recent advances in understanding the mechanisms of UV-radiation-induced degradation in materials and in assessing emerging technologies for their stabilisation against outdoor UV-degradation. A better understanding of the mechanisms of degradation will allow for innovative stabilisation approaches to be developed. Also assessed is information on the sustainability of the available and emerging UV stabilisation technologies.
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Core-shell nanoparticles of Co (0%, 3%, and 5%) doped Ni/NiO and incorporated (5 mg) graphene oxide (GO) sheets were synthesized by a sol-gel auto-combustion method. X-ray absorption near edge structure (XANES), extended X-ray absorption fine structure (EXAFS) and pair distribution function measurements were employed for the determination of the local structure and structural properties of the samples. Due to the effect of Co doping the bond lengths of all coordinate atoms were varied. The microstructural features in the core-shell structured particles were evaluated with high-resolution transmission electron microscopy (HRTEM). Magnetic properties of the samples revealed that both the interface of Ni/Co and NiO crystal lattices and the weight fraction of Ni have significant impact on their magnetic properties at 5 K to 300 K. Experimental results show that Co doping and GO incorporation into Ni/NiO suppress the antiferromagnetic charge ordering and lead to a spin-flop metamagnetic behavior at 5 K to 300 K temperatures. Above 5 K, the step-like transitions transform into broad ones. This step-like feature is correlated with the collapse of the balance between the magnetic energy and elastic energy at the core-shell interface. It is confirmed from M-T measurements that the blocking temperature of Ni/NiO was reduced with Co content.
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Actinomycetes, a Gram positive bacteria, well reported as a source of antibiotics, also possess potential to control various plant pathogens, besides acting as plant growth promoting agent. Chemicals in different forms are extensively being used in vegetable farming, adversely affecting the environment and consumer health. Microbial agent like actinomycetes can substantially replace these harmful chemicals, and have now started finding a place as an important input in to farming practices. Only selected vegetable crops belonging to 11 different families have been explored with use of actinomycetes as biocontrol and plant growth promoting agent till now. It provides ample opportunities to vegetable researchers, to further explore with use of this very important group of microorganisms, in order to achieve even higher production level of safe vegetables. Mycostop and Actinovate are two actinomycetes based formulations globally available for use in vegetable farming as a substitute for chemical formulations. Present review article has summarized the literature available on use of actinomycetes in vegetable farming. Existing wide gap in knowledge, and potential thrust areas for future research have also been projected.
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Actinobacteria/fisiología , Productos Agrícolas/crecimiento & desarrollo , Productos Agrícolas/microbiología , Desarrollo de la Planta , Verduras/crecimiento & desarrollo , Verduras/microbiología , Agricultura , Amaranthaceae/crecimiento & desarrollo , Amaranthaceae/microbiología , Amaryllidaceae/crecimiento & desarrollo , Amaryllidaceae/microbiología , Antibiosis , Apiaceae/crecimiento & desarrollo , Apiaceae/microbiología , Asparagaceae/crecimiento & desarrollo , Asparagaceae/microbiología , Asteraceae/crecimiento & desarrollo , Asteraceae/microbiología , Agentes de Control Biológico , Brassicaceae/crecimiento & desarrollo , Brassicaceae/microbiología , Cucurbitaceae/crecimiento & desarrollo , Cucurbitaceae/microbiología , Fabaceae/crecimiento & desarrollo , Fabaceae/microbiología , Enfermedades de las Plantas/prevención & control , Solanaceae/crecimiento & desarrollo , Solanaceae/microbiología , Zingiberaceae/crecimiento & desarrollo , Zingiberaceae/microbiologíaRESUMEN
Samples of energetic material TEX (C6H6N4O8) are studied using Raman spectroscopy and X-ray diffraction (XRD) up to 27 GPa pressure. There are clear changes in the Raman spectra and XRD patterns around 2 GPa related to a conformational change in the TEX molecule, and a phase transformation above 11 GPa. The molecular structures and vibrational frequencies of TEX are calculated by density functional theory based Gaussian 09W and CASTEP programs. The computed frequencies compare well with Raman spectroscopic results. Mode assignments are carried out using the vibrational energy distribution analysis program and are also visualized in the Materials Studio package. Raman spectra of the high pressure phases indicate that the sensitivity of these phases is more than that of the ambient phase.
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The Environmental Effects Assessment Panel (EEAP) is one of three Panels of experts that inform the Parties to the Montreal Protocol. The EEAP focuses on the effects of UV radiation on human health, terrestrial and aquatic ecosystems, air quality, and materials, as well as on the interactive effects of UV radiation and global climate change. When considering the effects of climate change, it has become clear that processes resulting in changes in stratospheric ozone are more complex than previously held. Because of the Montreal Protocol, there are now indications of the beginnings of a recovery of stratospheric ozone, although the time required to reach levels like those before the 1960s is still uncertain, particularly as the effects of stratospheric ozone on climate change and vice versa, are not yet fully understood. Some regions will likely receive enhanced levels of UV radiation, while other areas will likely experience a reduction in UV radiation as ozone- and climate-driven changes affect the amounts of UV radiation reaching the Earth's surface. Like the other Panels, the EEAP produces detailed Quadrennial Reports every four years; the most recent was published as a series of seven papers in 2015 (Photochem. Photobiol. Sci., 2015, 14, 1-184). In the years in between, the EEAP produces less detailed and shorter Update Reports of recent and relevant scientific findings. The most recent of these was for 2016 (Photochem. Photobiol. Sci., 2017, 16, 107-145). The present 2017 Update Report assesses some of the highlights and new insights about the interactive nature of the direct and indirect effects of UV radiation, atmospheric processes, and climate change. A full 2018 Quadrennial Assessment, will be made available in 2018/2019.