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In this work, solar-heating-induced temperature-based photocatalytic hydrogen evolution reaction (PC-HER) of different photocatalysts (TiO2 P25, g-C3N4, and their loaded Pt) was comprehensively stu...

Wheat growth has been severely affected by increases in global temperature. The Eastern Indo-Gangetic Plains of India face similar constraints due to the traditional wheat–rice cropping system where wheat planting is often delayed leading to high temperature induced terminal heat stress. Grain characters like grain length, width, area along with starch synthesis are affected severely during heat stress. Considering the importance of grain traits, we screened the response of 55 wheat genotypes under terminal heat stress conditions to ten grain characteristics. We found that the means of all the grain traits were reduced in heat stress conditions. The effect of heat stress shows a significantly reduced grain width and perimeter, but the extent of damage is less on different grain starch characteristics e.g., grain starch area (GSA), grain starch length (GSL) and grain starch volume (GSV). Stepwise multiple regression analysis revealed that grain starch area and grain volume are the best predictors of yield under optimum sowing date conditions whereas, grain width is the best predictor under late sowing date conditions. Interrelationship studies among ten grain characters showed that the genotypes with higher levels of grain starch characteristics (GSA, GSL and GSV) in combination with the five grain size characters (grain length, grain width, grain perimeter, grain area, A/B-type starch granules) under late sowing date conditions should be promoted for the cultivation of wheat in heat stress prone areas. The present study identified and recommends some heat tolerant wheat genotypes in terms of higher yield and grain starch characteristics namely, CRPW-33, CRPW-17, CRPW-12, CRPW-126 and CRPW-21.

Thirteen genotypes of Pearl millet (Pennisetum glaucum (L.) R. Br.) selected on the basis of heat tolerance were studied to see changes at biochemical and physiological levels. The plants were initially raised under normal condition in small plastic pots and 20 days old seedling were exposed at (40 °C for 4 hrs, 44 °C for 4 hrs and 46 °C for 2 hrs) in BOD incubator at Mandor to create the heat stress condition. After two days treatment data were recorded for MSI, chlorophyll content, antioxidative enzymes and MDA content. MSI, chlorophyll content and MDA decreased significantly due to heat stress while SOD, and CAT increased significantly under heat stress condition. The genotypic difference was also found significant. In some genotypes R/S increased while in some genotypes R/S ratio decreased under heat stress. The genotypes and PPMI 1053 and PPMI 1087 and HB 17-6 perform better having antioxidative enzymes. The better performance of these genotypes may be due to high RWC, MSI, chlorophyll, SOD, CAT and low MDA content under high temperature stress.

Stable colloidal zein nanoparticles (NPs) were synthesized by using controlled precipitation method. They were made fluorescence active by incorporating a small amount of fluorescence quinolinium surfactant. The incorporation of fluorescence surfactant provided both the colloidal stability and the fluorescence ability to determine the phase transition in zein NPs under the effect of temperature variation. Maintaining colloidal stability under the effect of temperature variation is an essential aspect of zein NPs applicability as a source of vegetarian protein supplement in different food suspensions. Different techniques such as fluorescence, DLS size, zeta potential, and FTIR measurements were applied to determine the influence of temperature on the colloidal stability of zein NPs. Zein NPs undergo phase transition well above room temperature while maintaining their size in nanometer range, and the phase transition temperature decreased with the amount of zein used in the synthesis of zein NPs. The results highlighted the potential use of zein NPs as a vegetarian supplement protein in different food products.

The use of buffers that mimic biological solutions is a foundation of biochemical and biophysical studies. However, buffering agents have both specific and nonspecific interactions with proteins. Buffer molecules can induce changes in conformational equilibria, dynamic behavior, and catalytic properties merely by their presence in solution. This effect is of concern because many of the standard experiments used to investigate protein structure and function involve changing solution conditions such as pH and/or temperature. In experiments in which pH is varied, it is common practice to switch buffering agents so that the pH is within the working range of the weak acid and conjugate base. If multiple buffers are used, it is not always possible to decouple buffer induced change from pH or temperature induced change. We have developed a series of mixed biological buffers for protein analysis that can be used across a broad pH range, are compatible with biologically relevant metal ions, and avoid complications that may arise from changing the small molecule composition of buffers when pH is used as an experimental variable.

Heterointerfaces coupling complex oxides exhibit coexisting functional properties such as magnetism, superconductivity, and ferroelectricity, often absent in their individual constituent. SrTiO3 (STO), a canonical band insulator, is an active constituent of such heterointerfaces. Temperature-, strain-, or mechanical stress-induced ferroelastic transition leads to the formation of narrow domains and domain walls in STO. Such ferroelastic domain walls have been studied using imaging or transport techniques and, often, the findings are influenced by the choice and interaction of the electrodes with STO. In this work, we use graphene as a unique platform to unveil the movement of oxygen vacancies and ferroelastic domain walls near the STO surface by studying the temperature and gate bias dependence of charge transport in graphene. By sweeping the back gate voltage, we observe antihysteresis in graphene typically observed in conventional ferroelectric oxides. Interestingly, we find features in antihysteresis that are related to the movement of domain walls and of oxygen vacancies in STO. We ascertain this by analyzing the time dependence of the graphene square resistance at different temperatures and gate bias. Density functional calculations estimate the surface polarization and formation energies of layer-dependent oxygen vacancies in STO. This corroborates quantitatively with the activation energies determined from the temperature dependence of the graphene square resistance. Introduction of a hexagonal boron nitride (hBN) layer, of varying thicknesses, between graphene and STO leads to a gradual disappearance of the observed features, implying the influence of the domain walls onto the potential landscape in graphene.

Poly(N-vinylcaprolactam) (PNVCL) polymers are stimuli-responsive and change their conformation in aqueous solutions upon changes in salt concentration, concentration of organic solvents, or temperature, making these molecules highly interesting for tailored release of drugs or fabrication of sensors or actuators. At lower critical solution temperature (LCST), PNVCL chains undergo a transition from a coil to a globule and become insoluble. In contrast to other polymers, however, PNVCL has received much less attention as to elucidating driving forces of its coil-to-globule transition at an atomistic level. Here, we show by a combined computational and experimental study that upon temperature increase, PNVCL chains dissolved in water experience an increase of intramolecular interactions between C3 and C4 of the caprolactam ring. Therefore, more favorable cavity formation energies and the increase of intramolecular interactions outweigh the loss in polar and hydrophobic solvation, and the loss of configurational entropy in the coil-to-globule transition and, thus, may be considered driving forces of the polymer’s collapse at LCST. These results are based on molecular dynamics simulations of in total 600 μs length and transition (free) energy computations that have been validated internally and against experimental data. We systematically tested the influence of the polymer’s length, concentration, tacticity, of the thermodynamic ensemble, and of the water model. Tacticity was found to be most influential, with atactic polymers showing the strongest tendency to collapse. The presented approach should be applicable to scrutinize at the atomistic level the impact of, for example, ion and polymer dispersity on the coil-to-globule transition of PNVCL, and the LCST behavior of other polymers.

The effect of light- and elevated temperature-induced degradation (LeTID) can be nonpermanently reversed by charge carrier injection below the degradation temperature (commonly used degradation temperatures are above ~70 °C). In this study, we show that the rate of temporary recovery depends strongly on the excess carrier density. We observe that the order of the reaction changes from pseudo-zero to first with increasing injection. The rate decreases slightly with increasing temperature. Since the samples can go through multiple degradation/recovery cycles without distinct changes in the degradation kinetics, the experimentally accessible recovered and degraded states are interpreted as manifestations of the equilibrium concentrations of the defect responsible for LeTID at different temperatures. Based on our observations, we argue that the process underlying LeTID degradation is the dissociation of a precursor rather than an association of two or more components. In light of the relation between LeTID susceptibility and bulk hydrogen concentration, we hypothesize that the LeTID precursor dissociates into the LeTID defect and monatomic hydrogen. Numerical simulations of the coupled rate equations including hydrogen interactions well reproduce the experimental observations; according to these results, the presence of a sink for the atomic hydrogen such as dopant atoms is paramount for the LeTID degradation.

Highly accurate high-throughput experimentation (HTE) data for a set of 21 silicon-bridged C2-symmetric ansa-zirconocenes in propene homopolymerization were collected and were used to develop quant...

Adsorption of polycyclic aromatic hydrocarbons (PAHs) on mineral surfaces plays an important role in many engineering fields, such as oil recovery and oil sands production. In this work, the adsorp...

The effect of storage conditions on changes of pH, total soluble solids (°Brix), colour, betalains (betacyanins and betaxanthins), and 5-hydroxymethylfurfural was investigated in apple-beetroot juices stored at 2, 7 and 20 °C for 120 days. The results obtained showed that the quality of apple-beetroot juice is significantly influenced by temperature and storage duration. Increasing storage time and temperature induced an apparent rise (P

The study is concerned with structural rearrangements in the crystals of heterospin complexes Cu(hfac)2 with nitroxide radicals LR (hfac is hexafluoroacetylacetonate, LR is 2-(1-R-1H-pyrazol-4-yl)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazole-3-oxide-1-oxyl, R is Et or Allyl) induced by increasing pressure from 10−4 to ∼1 GPa in the pressure-transmitting medium. An increase in the external pressure to only ∼0.03 GPa leads to the disappearance of the temperature-induced magnetic anomaly observed for these heterospin crystals under ambient conditions.

We have studied lifetime instabilities in p -type boron-doped mono-like silicon during light soaking (LS) and dark annealing (DA) at different temperatures, and their behavior upon LS/DA cycling at various degradation and regeneration stages. Despite having similar capture cross section ratios, it is found that the defects responsible for the degradation under illumination and in the dark could stem from two separate reactions, with hydrogen being the common precursor. A model for light and elevated temperature induced degradation (LeTID) is presented based on our experimental findings. It is proposed that hydrogen atoms originally bound in the silicon nitride layer are released into the silicon bulk above a certain firing temperature, which then interact with some other species in the silicon bulk under illumination, causing the LeTID degradation. During the cooling ramp of the firing process or extended DA, hydrogen in the silicon bulk starts to effuse into the ambient, reducing the amount of hydrogen remaining in the silicon bulk, and correspondingly affecting their LeTID behavior. The proposed model provides new insights to help understand complex LeTID behaviors reported in the literature, including its dependence on the firing profile, sample thickness, dopant type, and DA pretreatment.

Specimens for transmission electron microscopic (TEM) investigations were prepared from γ titanium aluminide alloys with Gallium and Argon ions using a focused ion beam (FIB) and a precision ion polishing system (PIPS). Preparation to electron transparency by Gallium ions alone leads to the formation of crystalline platelets of the α titanium phase at the specimen surfaces, revealed through conventional and high resolution (HR) TEM analysis. The platelets are assumed to precipitate from priorly formed amorphous layers. The required crystallisation temperature of about 480°C is generated through the ion bombardment implying that the γ titanium aluminides can be heated substantively during sputtering. The primary reason for this is the restricted transfer of heat away from the beam impact point when the specimen thickness comes close to the beam diameter. The formation of the platelets can be avoided by terminating the Gallium ion treatment prior to that, while providing for a sufficient thermal bonding of the specimen to the grid as well and polishing off the remaining material by Argon ions, which are much less focused and less energetic, so that the local heat peaks are reduced.

A mechanism to explain the lower onset strengthening temperature induced by CaCO$_3$ in alumina-based macroporous ceramics is proposed, which relies on hydrocalumite-like phase formation during processing. Close to 600$^\circ$C, such phases are decomposed to lime and mayenite (12CaO$\cdot$7Al$_2$O$_3$), where the latter, due to its intrinsic nanoporosity and high thermal reactivity, generates bonds between the ceramic particles at ~700$^\circ$C, resulting in microstructure strengthening. Based on this premise, the authors concluded that other Ca$^{2+}$ sources could act similarly. Indeed, compositions containing Ca(OH)$_2$ or CaO showed the same effect on the onset strengthening temperature, which reinforces the proposed mechanism. The results attained indicated that macroporous insulators could be thermally treated at lower temperatures, just to acquire enough mechanical strength for installation, finishing in situ their firing process. Besides that, lower sintering temperatures could be used to produce macroporous ceramics that would be applied in low thermal demand environments, e.g. aluminum industries.

Cold-pressed pumpkin and safflower seeds oils were stored at 2 ± 1 °C, 20 ± 1 °C and 40 ± 1 °C for 8 weeks. Measurements of lipid quality parameters were performed every 2 weeks. Throughout storage the emission and synchronous fluorimetric spectra of investigated oils were registered and colour L*, a*, b* parameters were determined. It was found that pumpkin oil, regardless of storage temperature, maintains high quality over the entire examined period. Safflower oil demonstrated relatively low oxidative stability, especially when stored at 20 and 40 °C. Evaluated activation energy of oxidation was 82.9 and 36.5 kJ/mol for pumpkin seed and safflower oil, respectively. Emission spectra determined the nature of changes occurring in investigated oils at all storage temperatures. Registered synchronous spectra connected with the principal component analysis (PCA) allowed the crucial factors influencing the oil quality to be identified. In addition, regression models were used to determine the parameters causing the observed colour changes of the examined products.

The hydrogen bond structure of water was examined by comparing the temperature dependent OH-stretching bands of water and aqueous NaClO4, KClO4, Na2SO4, and K2SO4 solutions. Results called attention to the role of cations on top of the importance of anions determining the emerging structure of a multi-layered system consisting single water rings or multi-ring water-clusters.

Physiologia plantarum 174(1), e13602 (2021). doi:10.1111/ppl.13602 special issue: "This article also appears in: Plant Sugar Metabolism, Transport and Signalling in Challenging Environments", Published by Wiley-Blackwell, Oxford [u.a.]

High temperature can induce the production of 2n gametes and aborted pollen during microsporogenesis in Populus canescens. However, the mechanism by which high temperature induces pollen abortion remains unknown. Here, pollen abortion was induced by exposing male flower buds of P. canescens to 38 and 41 °C; pollen morphology, meiotic abnormalities, defects of the meiotic microtubular cytoskeleton, and tapetum development were characterized, and expression analysis of the Actin gene was conducted. We found that the dominant meiotic stage, temperature, and duration of treatment significantly affected the percentage of high temperature-induced aborted pollen. Damaged spindle microtubules and depolymerized microtubular cytoskeletons were observed, which resulted in many lagging chromosomes at anaphase Ⅰ and Ⅱ, as well as aneuploid male gametes and micronuclei, generating aborted pollen grains. Tapetum disintegration was also delayed. However, the anther dehisced normally, and some viable pollen grains were released, suggesting that the delayed degradation of the tapetum was not responsible for pollen abortion. A significant reduction in PtActin gene expression was detected in treated cells, indicating that spindle actin was disrupted. The spindle actin appeared to protect cells against chromosome segregation errors during meiosis.

A series of polyimide (PI) films with a high-temperature-induced shape memory effect and tunable properties were prepared via the facile random copolymerization of 4,4′-oxydianiline (ODA) with 4,4′-(hexafluoroisopropyl)diphthalic anhydride (6FDA) and 4,4′-oxydiphthalic anhydride (ODPA). The trigger temperature can be controlled from 294 to 326 °C by adjusting the ratio of monomers. The effects of monomer rigidity on the chain mobility, physical properties, and shape memory performance of as-prepared copolyimide were systematically investigated. The introduction of ODPA could enhance the mobility of PI macromolecular chains, which made chain entanglement more likely to occur and increased the physical crosslinking density, thereby improving the PI’s shape recovery up to 97%. Meanwhile, the existence of 6FDA enabled PI films to set quickly at low temperatures with a shape fixation of 98%. The shape memory cycling characteristics of the polyimide films are also studied, and the relationship between the PI chemical structure and the film properties are further discussed.

An ultralight bacterial cellulose/polypropylene-graft-maleic anhydride (BC/PP-g-MA) composite cryogel was fabricated using a facile temperature induced phase separation (TIPS) method followed by fr...

International audience; One of the causes of decrease in the performance of silicon-based solar pannels is linked to light and elevated temperature induced degradation (LeTID). Even if experimental evidence shows that different defects in the bulk material of the modules are involved in the mechanisms behind LeTID, its origins remain unresolved. First-principles methods result in powerful tools to understand this degradation at the nano and microscopic levels. In the present work we propose an approach to model LeTID precursors mechanisms by using ab initio methodology.

This study presents aging of backsheet materials that were stored for 17 years in the dark at room temperature. The material properties were measured and compared to the results from right after production. After 17 years of storage the strain at break values decreased significantly for all materials. As chemical aging phenomena were excluded, a disentanglement of the polymer chains in the amorphous phase would explain the observed changes. Especially for PVDF the change in the mechanical behavior is considered as very critical and possibly would lead to cracking during operation.

ABA antagonists have potential application as growth regulators to improve germination and seedling growth at low temperatures for oilseeds and pulses grown in regions with short seasons such as those in western Canada. Towards development of practical ABA antagonists, a series of 3′-substituted ABA analogs were synthesized and screened in seed germination assays in canola (Brassica napus), lentil (Lens culinaris), and soybean (Glycine max) at low temperature and in overcoming exogenous ABA. The most promising analog, ABA 1009, was selected for further germination testing of dose responses in canola, lentil, and soybean. Analog ABA 1009 at 100 µM was effective in overcoming ABA (10 µM)-induced inhibition for canola, lentil, and soybean germination at ambient temperature, and also promoted germination at low temperature for canola (5 °C).

Thermoresponsive interpenetrating networks (IPNs) were prepared by sequential synthesis of a biohybrid network of star-shaped poly(ethylene glycol) [starPEG] and heparin and a poly(N-isopropylacryl...

Anti-oxidative system in plants comprising of enzymatic and non-enzymatic antioxidants imparts stress tolerance by scavenging/detoxification of excess reactive oxygen species (ROS) produced under high temperature stress. Present investigation deals with the estimation of metabolites and anti-oxidative enzyme activities in four inbred maize lines; NSJ221, NSJ189, PSRJ13099 and RJR270 in response to high temperature stress imposed at reproductive stage by staggered sowing. An increase in H2O2 and malondialdehyde (MDA) was observed in all the genotypes, however the increase was higher in PSRJ13099 and RJR270. The activities of studied enzymes increased in NSJ189 and NSJ221 while a decrease was observed in PSRJ13099 and RJR270. Under heat stress isoforms of SOD increased in NSJ189 and NSJ221 while a concomitant decrease was observed in PSRJ13099 and RJR270. Two new SOD-isoforms were also observed in NSJ221. GPX showed more number of high mobility isoforms with low activity in NSJ221 and less mobile isoforms with higher activity in both NSJ189 and NSJ221. Whereas, PSRJ13099 and RJR270 showed decrease band intensity of less mobile GPX-isoforms under heat stress. Activity of CAT-isoforms increased to a similar extent across the genotypes under heat stress. In case of non-enzymatic antioxidants, non-protein thiols increased in all the genotypes while the level of carotenoids depleted in all the genotypes except NSJ221. Ascorbate (AsA) levels depleted in PSRJ13099 and RJR270 and increased in NSJ189 and NSJ221 under heat stress. Understanding the intricate regulatory pathways in crop plants under heat stress will help in developing genotypes with enhanced stress tolerance.

We provide experimental evidence that photoalignment at the nematic liquid crystal (NLC)-polymer interface cannot be simply considered as a two-dimensional process. Moreover, our experiments clearly indicate that the photoaligning process does not depend on the individual properties of the NLC material and those of the interfacing polymer exclusively. The polymer and the NLC layer interact, i.e., the polymer-liquid crystal interface should be regarded as a coupled system, where the two components mutually influence each other. Furthermore, we show that the temperature induced anchoring transition also has to be taken into account for the complete description of the photoalignment mechanism.

Two techniques for the nucleation and growth of single crystals of biological macromolecules are proposed. The first one utilizes a very slow temperature shift at a capillary point where the crystal is to be grown. This allows to suppress an undesirable multiple nucleation. The second technique includes several local rapid temperature changes (a temperature “shock”) forcing the nucleation at the given point. These techniques were successfully tested while growing single crystals of lysozyme and xylanase respectively.

Ferromagnetic semiconductors (FMSs) featuring a high Curie transition temperature (Tc) and a strong correlation between itinerant carriers and localized magnetic moments are of tremendous importanc...

The heat capacity Cp is calculated from the temperature-induced and pressure-induced Raman frequency shifts by means of the mode Gruneisen parameter for the I-II transition of solid benzene, naphthalene and anthracene. For this calculation, contributions to Cp are considered due to the six lattice modes of solid benzene, six librational modes of naphthalene and, six phonons and nine vibrons of anthracene with their mode Gruneisen parameters at various temperature (P=0) and pressures (T=300 K). Our calculated Cp explains the observed behavior of the I–II transition in solid benzene and also of naphthalene and anthracene. Temperature dependence of the entropy difference is calculated from the heat capacity for those hydrocarbons, which can be compared with the observed data. Our results indicate that the heat capacity Cp can be calculated as functions of temperature and pressure from the spectroscopic parameters, in particular, the Raman frequency shifts as we have studied here for hydrocarbons.

Ceiling gas temperature is one of the most important factors for heat detection and alarm once an undesirable fire along with releasing hot and toxic smoke is erupted in a building. The impinging flame characterized by the unburnt fuel burning along the ceiling has received much attention in recent years as it poses a greater threat to the ceiling structure, devices and trapped people than the non-impinging flame. Many studies have been focused on the ceiling gas temperature induced by a single flame, while little effort has been put with respect to the multiple flames. The interaction between multiple flames might lead to flames tilt to each other and even merge together with small spacings, resulting in different ceiling gas temperature distribution from the single flame. The aim of this experimental work is to investigate the ceiling gas temperature decay profile induced by two impinging flames. Propane was used as the fuel. The heat release rate (HRR), burner edge spacing and ceiling height above the fuel were overall changed. The ceiling gas temperatures along the direction of changing spacing were measured to determine the impingement point position and temperature decay profile. The results showed that the impingement point position is dependent on the HRR and the spacing as well as the ceiling height, while the maximum gas temperature is weakly affected by the spacing. The established correlation reveals that the maximum excess temperature increases first and then maintains unchanged with increasing the HRR normalized by the ceiling height. The plume radius proposed for the single impinging flame is not enough to characterize the ceiling gas temperature of two impinging flames. A new correlation for temperature decay profile induced by two impinging flames is therefore proposed and validated using the experimental results.

We presented two new ABX3 postperovskite coordination polymers, (C5H13NCl)[M(dca)3] (dca = N(CN)2–, M = Mn2+ for 1 and Cd2+ for 2), as well as their phase transition behaviors disclosed by using differential scanning calorimetry measurements, variable-temperature single-crystal X-ray analyses, dielectric measurements, and Hirshfeld surface analyses. Both 1 and 2 have same structure (Cmcm) at room temperature, in which their A-site organic cations are fourfold disordered about two mirror planes and undergo order–disorder phase transition mainly caused by the freezing of A-site cations upon cooling. The different metal ions endow them distinct structural flexibility, resulting in different phase transition behaviors and dielectric responses; that is, the smaller and coordinatively rigid Mn2+ ion results in two-step Cmcm (Z = 4) ↔ Pbcm (Z = 4) ↔ Pbca (Z = 8) transitions accompanied with obvious dielectric relaxation, whereas the larger and coordinatively flexible Cd2+ ion results in one-step Cmcm (Z = 4) ↔ P...

Elevated temperature usually plays a destructive role in supramolecular complexes. At higher temperature, folded proteins tend to unfold and supramolecular assemblies tend to disassemble. In contrast, histidine kinases are able to perform a different function at higher temperature. This results from temperature-induced large amplitude conformational changes. However, similar phenomena have rarely been reported for synthetic receptors. Herein, we report that the conformationally adaptive oxatub[4]arene is able to show a conformational response to temperature change in the presence of an appropriate guest. By employing rotaxane synthesis, the host's conformation in the complex at different temperatures can be fixed. The resulting rotaxanes with different host conformations have been carefully characterized by using 2D NMR spectroscopy, mass spectrometry, and X-ray single crystallography.

Light- and elevated-temperature-induced degradation (LeTID) in p-type multicrystalline silicon has a severe impact on the effective minority carrier lifetime of silicon and remains a crucial challenge for solar cell manufacturers. The precise cause of the degradation is yet to be confirmed; however, several approaches have been presented to reduce the extent of degradation. This paper presents insights on the impact of thermal budgets and cooling rates during post-firing illuminated anneals and their role in changing the lifetime and mitigating LeTID for thermal processes between 350 and 500 °C. We demonstrate that the thermal budget of these processes plays a crucial role in LeTID suppression and that the cooling rate only plays a role during short treatment durations (≤1 min). For the parameter space studied, we show that annealing for an appropriate time and temperature can both enhance the minority carrier lifetime and completely suppress the LeTID, with the injection-dependent Shockley–Read–Hall lifetime analysis indicating that the recombination activity of the LeTID defects in the bulk has been eliminated. Finally, this paper demonstrates a process that results in a stable lifetime after 800 h of conventional light-soaking at 75 °C.

We performed an extensive study of light induced degradation experiments in PERC solar cells made of Boron doped Cz Silicon material from several experimental crystals. Strong LeTID (Light and Elevated Temperature Induced Degradation) amplitudes were found in cells originating from the top and tail part of the crystals. A statistical analysis reveals a strong correlation to the bulk concentration of Aluminium in cells originating from wafers close to the tail. Close to the top, the LeTID effect is strongly enhanced whenever Oxygen precipitation occurs in the cell process.

The development of light-electricity conversion in nanomaterials has drawn intensive attention to the topic of achieving high efficiency and environmentally adaptive photoelectric technologies. Besides traditional improving methods, we noted that low-temperature cooling possesses advantages in applicability, stability and nondamaging characteristics. Because of the temperature-related physical properties of nanoscale materials, the working mechanism of cooling originates from intrinsic characteristics, such as crystal structure, carrier motion and carrier or trap density. Here, emerging advances in cooling-enhanced photoelectric performance are reviewed, including aspects of materials, performance and mechanisms. Finally, potential applications and existing issues are also summarized. These investigations on low-temperature cooling unveil it as an innovative strategy to further realize improvement to photoelectric conversion without damaging intrinsic components and foresee high-performance applications in extreme conditions.

Generally, the purification performance of bioreactors could be influenced by temperature variation via shaping different microbial communities. However, the underlying mechanisms remain largely unknown. Here, the variation trends of microbial communities in three sequencing batch biofilm reactors (SBBRs) under four different temperatures (15, 20, 25, 30 °C) were compared. It was found that temperature increment led to an obvious enhancement in nutrient removal which was mainly occurred in the aerobic section. Meanwhile, distinct differences in dominant microbial communities or autotrophic nitrifiers were also observed. The performance of the SBBR reactors was closely associated with nitrifier communities since the treated wastewater was characterized by a severe lack of carbon sources (mean effluent COD ≤ 14.4 mg/L). Spearman correlation unraveled that: most of the differentiated microbes as well as the dominant potential functions were strongly associated with nutrient removal, indicating the temperature-induced difference in microbial community well explained the distinction in purification performance.

Objective To establish a temperature-induced chitosanase bacterial cell surface display system to produce chitooligosaccharides (COSs) efficiently for industrial applications. Results Temperature-inducible chitosanase CSN46A bacterial surface display systems containing one or two copies of ice nucleation protein (InaQ-N) as anchoring motifs were successfully constructed on the basis of Escherichia coli and named as InaQ-N-CSN46A and 2InaQ-N-CSN46A. The specific enzyme activity of 2InaQ-N-CSN46A reached 886.33±0.81 U/g cell dry weight, which was 45.6% higher than that of InaQ-N-CSN46A. However, few proteins were detected in 2InaQ-N-CSN46A hydrolysis system. Therefore, 2InaQ-N-CSN46A had higher hydrolysis efficiency and stability than InaQ-N-CSN46A. GPC revealed that under the optimum enzymatic hydrolysis temperature, the final products were mainly chitobiose and chitotriose. Chitopentaose accumulated (77.62%) when the hydrolysis temperature reached 60 ℃. FTIR and NMR analysis demonstrated that the structures of the two hydrolysis products were consistent with those of COSs.Conclusions In this study, chitosanase was expressed on the surfaces of E. coli by increasing induction temperature, and chitosan was hydrolysed directly without enzyme purification steps. This study provided a novel strategy for industrial COSs production.