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Intrinsic and extrinsic strains are leveraged to synthesise vanadium oxide complexes that undergo IMT near room temperature. The complexes are studied and used to modulate the IR radiation of a hot object as a proof-of-concept application.

Apoptosis and macroautophagy/autophagy, two important processes for host intracellular immunity against virus infection, are commonly deployed by arbovirus to promote its survival within an arthropod vector. Numerous studies have focused upon either apoptosis or autophagy initiated by arbovirus infection, with limited insight into the mechanisms underlying orchestration of vector immune tolerance to arbovirus. Using plant tomato yellow leaf curl virus (TYLCV)-infected whiteflies we identified a master regulator, PEBP4, that can be hijacked by the TYLCV coat protein (CP) and in turn synchronously activates apoptosis and autophagy. Once TYLCV invades a whitefly cell, the viral CP captures membrane-localized PEBP4, stabilizing PEBP4 association with RAF1. The triple complex blocks a MAPK phosphorylation cascade and triggers apoptosis. Simultaneously, virus CP competes for PEBP4 binding, promoting the disassociation of PEBP4 from ATG8 and initiating autophagy. The activation of autophagy degrades invasive TYLCV, whereas apoptosis increases the viral load by antagonizing autophagy. Amplification of autophagy intensity can eliminate arbovirus load but enhances whitefly fitness cost. In contrast, suppression of autophagy causes the viral load to exceed the vector capacity, which is also detrimental to whitefly survival. Thus, only mild intracellular immunity balanced by apoptosis and autophagy permits long-term coexistence between vectors and arboviruses. ABBREVIATIONS: CP: coat protein; MAPK: mitogen-activated protein kinase; PEBP: phosphatidylethanolamine binding protein; TYLCV: tomato yellow leaf curl virus.

The self-terminated, layered structure of van der Waals materials introduces fundamental advantages for infrared (IR) optoelectronic devices. These are mainly associated with the potential for low noise while maintaining high internal quantum efficiency when reducing IR absorber thicknesses. In this study, we introduce a new van der Waals material candidate, zirconium germanium telluride (ZrGeTe4), to a growing family of promising IR van der Waals materials. We find the bulk form ZrGeTe4 has an indirect band edge around ∼0.5 eV, in close agreement with previous theoretical predictions. This material is found to be stable up to 140 °C and shows minimal compositional variation even after >30 days storage in humid air. We demonstrate simple proof-of-concept broad spectrum photodetectors with responsivities above 0.1 AW-1 across both the visible and short-wave infrared wavelengths. This corresponds to a specific detectivity of ∼109 cm Hz1/2 W-1 at λ = 1.4 μm at room temperature. These devices show a linear photoresponse vs illumination intensity relationship over ∼4 orders of magnitude, and fast rise/fall times of ∼50 ns, also verified by a 3 dB roll-off frequency of 5.9 MHz. As the first demonstration of photodetection using ZrGeTe4, these characteristics measured on a simple proof-of-concept device show the exciting potential of the ZrGeTe4 for room temperature IR optoelectronic applications.

A simple method was used to synthesize magnetic xanthate-modified chitosan/polyacrylic acid hydrogels that were used to remove heavy metal ions from an aqueous solution. Xanthate modification of chitosan significantly improved adsorption performance: individual adsorption capacities of the hydrogel for Cu(II), Cd(II), Pb(II), and Co(II) ions were 206, 178, 168, and 140 mg g−1, respectively. The magnetic hydrogels had good regeneration ability and were effectively separated from the solution by use of a magnet. Adsorption kinetic data showed that the removal mechanism of heavy metal ions from the solution by magnetic hydrogels occurs mainly by chemical adsorption. The equilibrium adsorption isotherms were well-described by the Freundlich and Langmuir equations. Positive values were found for the Gibbs standard free energy and enthalpy, indicating an increase in the disorder at the solid–liquid interface during adsorption. Magnetic xanthate-modified chitosan-based hydrogels that exhibit high adsorption efficiency, regeneration, and easy separation from a solution have broad development prospects in various industrial sewage and wastewater treatment fields.

Due to the excellent optical properties and great application prospects in the optical field, both pyrene compounds (PCs) and chiral liquid crystal have attracted extensive attention in theoretical...

As an important modeling parameter in multi-point geostatistics, training images determine the modeling effect to a great extent. It is necessary to evaluate and optimize the applicability of candidate training images before modeling by multi-point geostatistics. Conventional two-dimensional training images can’t describe the overlapping relation of sedimentary facies in space, and there is a deficiency in describing the event relation of single data. This paper puts forward a new training image optimization method. The basic idea is to arrange and analyze sand bodies filled with sedimentary sand bodies in point dams and river channels in different periods. The method of obtaining three-dimensional training images is to use sand thickness maps and sedimentary facies maps for spatial constraints. The simulation test shows that compared with the sedimentary facies model obtained from two-dimensional training images, the sedimentary facies model obtained from three-dimensional training images through multi-point geostatistics has high compatibility and is more in line with geological understanding. On the basis of fully understanding the development characteristics of the sedimentary system and quantitative geometry of sedimentary body in the study area, sedimentary microfacies models based on sequential indicator simulation method and target simulation method are established, respectively. By comparing and analyzing the sedimentary microfacies models established by three different methods, the results show that the multi-point geostatistics can stably present the planar distribution characteristics and overlapping spatial relationship of sedimentary microfacies and reproduce the complex spatial structure and geometric shape of fluvial facies. The model established by this method is more in line with the geological sedimentary model.

Fingerprints remain topologically unchanged in one's whole life, and therefore, have been used as a means to biometrically identify individuals in forensic investigations, law enforcement and access control. Appropriate methods are essential to obtain high-quality fingerprint images. In this contribution, an aggregation-induced emission luminogen tetraphenylethene-based dye FLA-2 was synthesized and characterized for the visualization of latent fingerprints (LFPs). LFPs can be directly visualized by incubating with the dye FLA-2 solution. And, after a cyanoacrylate fuming method pre-treatment stage, fine fingerprint structures can be obtained from level-1 to level-3 details. Two methods were compared using resolution, fluorescence intensity, and scanning electron microscopy imaging to investigate the influence of the cyanoacrylate fuming method pre-treatment stage. Furthermore, the visualization of old LFPs (7 d, 16 d and 30 d) on glass slides, aluminum foil and coin substrates also became effective after the pre-treatment step. The fluorescent LFP images mentioned above were all validated by using an automated fingerprint identification system obtaining positive matches. These results demonstrate the potential of this method to be applied to visualizing LFPs in the field of public security.

The synthesis of single-component, all-conjugated D–A diblock copolymers that exhibit high photovoltaic activity remains a significant challenge. To date, the synthesis of all-conjugated block copolymers typically produces a mixture of donor and acceptor homopolymers, diblock copolymers, ternary block copolymers or multi-block copolymers. In this work, we report the use of an A–B type monomer to synthesise a diblock copolymer. Importantly, by avoiding AA + BB polymerization, we have eliminated the production of ternary block and multi-block copolymers. In addition, the donor and acceptor blocks had orthogonal solubility in order to increase the purity of the block copolymer and give significant nanoscale phase separation. Two single-component diblock copolymers (P3HT-b-TBTF8 and P3HT-b-F8TBT) were synthesized, of which different molecular weights were obtained using Soxhlet extraction and preparative GPC. Both copolymers exhibited good thermal stability and effective self-aggregation. Thermal annealing was found to reduce the self-aggregation time and enhance the crystallization of the P3HT block, which effectively reduced the self-aggregation of the polymers. The power conversion efficiency of a single component active layer based P3HT-b-F8TBT photovoltaic device reached 1.22%. The higher efficiency of this device was thought to be caused by the linkage between the donor and acceptor blocks, whose P3HT and PF8TBT chains are separated by the wider bandgap F8 unit. Moreover, the unique molecular structure and self-assembly properties of these diblock copolymers will allow them to be used as model materials for further studies on charge and energy transfer in photovoltaic devices.

The derivatization of perylenediimides (PDIs) by bay decoration is essential for the development of PDI-based semiconductors owing to their excellent photoelectric properties. Herein, four bis-azabenz-annulated PDIs (bis-AzaBPDIs) are concisely synthesized in high yields through ultraviolet-induced photocyclization, where the reaction processes including aldimine condensation, cyclization, and oxidative re-aromatization are investigated. The optical characterizations and theoretical simulation reveal that the unique properties of the four bis-AzaBPDIs are comparable to their parent PDI. Organic field effect transistors with compounds 2, 3, or 4 as active layers indicated that all compounds showed unipolar electron transport properties with the mobilities of 1.1×10

Photodetectors formed with layered two-dimensional (2D) materials have shown significant potential for integration with photonic circuits, offering fast, high responsivity and low noise detection over a broad range of optical wavelengths. However, only preliminary trials of this concept have been performed on emerging photonics platforms such as lithium niobate on insulator (LNOI). In this study, a novel architecture consisting of ≈15 nm thick layered black phosphorus (bP) photoconductors draped over LNOI waveguides is demonstrated. The performance of these detectors is studied across the telecom bands at room temperature, and a high extrinsic responsivity of 148 mA W−1 is measured at λ = 1550 nm under low bias conditions (VDS = 0.3 V). The spectral response of the detectors is broad allowing the response of other photonic components, such as fiber-to-chip grating couplers, to be characterized in situ, without need to out-couple the light. Finally, the speed of the bP detectors is found to be beyond our instrumentation, setting 100 ns as an upper-limit rise/fall time, with the actual speed of the bP detector likely to be much faster., Advanced Optical Materials, 11 (2), ISSN:2195-1071

The self-terminated, layered structure of van der Waals materials introduces fundamental advantages for infrared (IR) optoelectronic devices. These are mainly associated with the potential for low noise while maintaining high internal quantum efficiency when reducing IR absorber thicknesses. In this study, we introduce a new van der Waals material candidate, zirconium germanium telluride (ZrGeTe

A series of conjugated donor–acceptor (D–A) block copolymers (BCPs) were synthesised using a one-pot Stille coupling polycondensation reaction. This involved reaction between a series of mono-bromo-functionalised Poly3-hexylthiophene (P3HT) polymers (P3HT-Br, Mn : 17, 21 and 43 kg/mol) and [N, N′-bis(2-decyl-tetradecyl)-1,7-dibromo-3,4,9,10-perylene diimide (PBI) and [2,5-bis(trimethylstannyl)-thiophene] (T) monomers. Purification using preparative gel permeation chromatography (GPC) removed any excess P3HT and resulted in BCPs with low polydispersity index values. The P3HT-b-PBIT BCPs were characterised using 1H-NMR and Fourier-transform infrared spectroscopy. When compared to a P3HT/PBIT polymer blend, the D–A BCP films exhibited a remarkably fine structure with a nanoscale morphology. These results indicated that these D–A BCPs have the potential for use as nanostructured active layers in polymer solar cells.

All-conjugated donor-acceptor block copolymers (BCP) were synthesized in a one-pot reaction by a Stille coupling polycondensation through a terminal functional polymer copolymerization process. Mono bromo end-functionalized P3HT samples with various molecular weights (P3HT-Br, Mn: 5, 9, and 26 kg/mol) were copolymerized with AA (N,Nʹ-Bis(2-decyl-1-tetradecyl)-2,6-dibromonaphthalene-1,4,5,8-tetracarboxylic acid bisimide, NDI) and BB (5,5′-bis(trimethylstannyl)-2,2′-bithiophene) type monomers. Further purification by preparative GPC removed excess P3HT to yield block copolymers of low polydispersities with different donor and acceptor block chain lengths. The block copolymers were characterized by 1H-NMR and UV–vis absorption and FTIR spectroscopy. The optical properties, film morphologies, and optoelectronic properties of the block copolymer were strongly influenced by the donor and acceptor block chain lengths. Furthermore, the fully conjugated D-A block copolymer films exhibited fine structures, smooth film morphologies, and better OPV performance than those features of P3HT/PNDIT2 polymer blends. In polymer solar cells based on the various block copolymer as active layers, the device power convention efficiency was improved by maintaining the acceptor block content at 40–50 kg/mol and increasing the P3HT chain from 5 to 26 kg/mol.

Direct C-H arylation is an approximate tool for synthesis of thiophene-diketopyrrolopyrrole (DPP) derivatives, because of better atomic economy, fewer synthetic steps and being environmental friendly. In this work, DPP containing linear structured small molecule TBT(DPPT2)2 are facilely synthesized in high yield by the C-H direct arylation, other small molecule TBT(DPP)2 are synthesized thought stille cross-crouping reaction. Thermal, optimized geometries, electrochemical, photo-physical properties and film morphology of two materials are studied and solution-coated organic field effect transistors (OFETs) are preparated. TBT(DPPT2)2 have wider band gaps and enhanced electronic defects compare to TBT(DPP)2. Both TBT(DPP)2 and TBT(DPPT2)2 demonstrated typical p-type transport with average hole mobility of 1.26 × 10−3 and 9.58 × 10-4 cm2 V-1 s-1 respectively.

Apoptosis and autophagy are two most prominent forms of programmed cell deaths (PCD) that have been implicated in antiviral immunity in vertebrate and plant hosts. Arboviruses are able to coexist with its arthropod vectors by coordinating the PCD immunity, but the regulatory mechanism involved is largely unknown. We found that the coat protein (CP) of an insect-borne plant virus TYLCV directly interacted with a phosphatidylethanolamine-binding protein (PEBP) of its insect vector whitefly to negatively influence the MAPK signaling cascade. As a result, the apoptosis was activated in whitefly which increased viral loading. Simultaneously, the PEBP4-CP interaction liberated ATG8, the hallmark of autophagy initiation, and eliminates arbovirus. Furthermore, apoptosis-promoted virus loading was compromised by agonist-induced autophagy, but autophagy-associated suppression on virus loading was unaffected by apoptosis agonist or inhibitor, suggesting that virus loading was predominantly determined by autophagy rather than by apoptosis. Our results demonstrated that maintaining a mild immune response by coordinating apoptosis and autophagy processes presumably could facilitate coexistence of the arbovirus and its insect vector. Taken together, immune homeostasis shaped by two types of PCD may facilitate the arbovirus preservation within the insect vector.Graphical abstractHighlightsInteraction between whitefly PEBP4 and TYLCV CP suppresses phosphorylation of MAPK cascade, activating apoptosisTYLCV CP liberates PEBP4-bound ATG8, resulting in lipidation of ATG8 and initiation of autophagy.PEBP4 balances apoptosis and autophagy in viruliferous whitefly to optimize virus loading without obvious fitness cost.

By introducing various low concentrations of Iridium complexes to the famous donor polymer of PTB7-Th backbone, new heavy metal containing terpolymers have been demonstrated. When blended with PC71BM, an obvious increase of power conversion efficiency (PCE) is obtained in 1 mol% Ir containing polymer for different photovoltaic devices either using Ca or PDIN as cathode interface layers. The impact of molecular weight on the photovoltaic performance has been particularly considered by using three batches of control polymer PTB7-Th to ensure a fair and more convincing comparison. At similar molecular weight conditions (Mn: ~60 kg mol−1, Mw: 100–110 kg mol−1), the 1 mol% Ir containing PTB7-ThIr1/PC71BM blends exhibits enhanced PCE to 9.19% compared with 7.92% of the control PTB7-Th. Through a combination of physical measurement, such as optoelectrical characterization, GIWAXS and pico-second time-resolved photoluminescence, the enhancement are contributed from comprehensive factors of higher hole mobility, less bimolecular recombination and more efficient slow process of charge separation. Only 1 mol% of Ir complex can do the trick to greatly enhance the efficiency of PTB7-Th: fullerene polymer solar cell from 7.9 to 9.2%. A collaborative research led by Youtian Tao from Nanjing Tech University, China shows that the power conversion efficiency of PTB7-Th: fullerene polymer solar cell can be enhanced by conjugating extremely low ratio of heavy metal Ir complex via ancillary ligand. The conclusions have proved robust for PTB7-Th with different molecular weight, different Ir complex concentrations and different cathode interface materials such as calcium or PDIN. These results prove the importance of heavy metal complex for highly efficient photovoltaic devices and demonstrate a promising design approach toward more efficient photovoltaic polymer donor materials.

A dynamic surface pattern with tunable liquid crystalline texture and fluorescence in response to external stimulus can enable information recording and reading. Therefore, such patterns are widely used in the field of information security and anti-counterfeiting. A higher level of security in anti-counterfeiting is extremely desirable but challenging, herein, the chiral liquid crystalline networks (CLCN) used for anti-counterfeiting displaying both dynamic reversible Grandjean textures and fluorescence were dexterously designed and prepared by graft copolymerization of polymethylhydrosiloxane (PMHS), nematic liquid crystal M1, chiral crosslinker M2 and organic fluorescent pyrene compounds M3. The CLCN can emit blue-fluorescence when irradiating with ultraviolet light. More importantly, the Grandjean textures and fluorescence can be simultaneously and precisely adjusted by temperature. The as-prepared CLCN display reversible Grandjean textures during the heating and cooling process from the intrinsic chiral arrangement of CLCN. The discrete pyrene chromogenic segments in CLCN matrix enable the tunable photoluminescence by temperature, furthermore, the CLCN present highly sensitive photoluminescence evolution. The dynamic reversible Grandjean textures and fluorescence make the smart materials promising candidates in anticounterfeiting, providing a versatile strategy to fabricate intelligent optical anti-counterfeiting materials.

Functional genomics of microalgae have undergone tremendous progress and have a huge impact for streamlining the algal cultivation technology; however, the rational utilization of algal genomes for discovering the strategies to combat algal culture contamination remain unexplored. Genome comparison of fungi and microalgae allowed us to find insights into the possible distinctions of key enzymes and genetic structural of sterol biosynthetic pathway, which are the targets for commercial fungicides. By further screening and characterizing chemical inhibitors targeting selected sterol biosynthetic enzymes, a species-specific contamination control method tailored to oleaginous Nannochloropsis oceanica has been developed. With a concentration of as low as 1 μg/ml, triticonazole, a sterol 14-demethylase inhibitor, was capable of effectively eliminating contaminated fungi and potential invasive algal strains, and able to stimulate the growth of desired microalgal species. These findings suggest that the crossing kingdom genome comparison helps to identify genetic distinctions which can be utilized to select appropriate and customized microbial contamination control approach for culturing individual microalgal species with desired production traits.

We synthesized a rhodamine-based fluorescent probe 1 , which could be used for the optical detection of Fe 3+ . Compared with other commonly coexistent metal ions in aqueous system, it exhibited high sensitivity and selectivity for Fe 3+ , and the detection limit was only 4.2 × 10 −8 M. In addition, the rapid enhancement of fluorescence intensity on addition of Fe 3+ provided a good method for the detection of Fe 3+ . What’s more, the colour change was visible and distinct, so it could be used for the naked-eye detection of Fe 3+ . Furthermore, the fluorescent probe was proved to be effective when used for sensing Fe 3+ in living cells and zebrafish. These results showed its values in biological aspects.

A tetraphenylethene-based dye (FLA-1) was used to develop for enhancing the visualization of the latent fingerprints on the surfaces of various substrates. The resolution of the fingerprints visualized by the probe FLA-1 is enough to offer a positive match according to the information supplied from a police database. Experimental results confirm the accuracy of using the probe for LFPs detection.

A series of novel hyperbranched polymers (HBPs) consisting of a 2,7-subsituted 9-(heptadecan-9-yl)-9H-carbazole unit (A2+A2’) and a tetra-substituted green thermally activated delayed fluorescence (TADF) dye of 2,3,5,6-tetra(9H-carbazol-9-yl)-4-pyridinecarbonitrile (4CzCNPy, B4) have been synthesized via Suzuki cross-coupling reaction following an “A2+A2’+B4” method. The polymers are named according to the polymerization ratio of 4CzCNPy monomer (5 mol%, 10 mol% and 15 mol% for HBPs of P2−P4 respectively, and 0 mol% for the control linear polymer P1). Their thermal, optoelectronic and electrochemical properties have been characterized by a combination of techniques. All the polymers exhibit high thermal stability with the decomposition temperatures (Td) above 400 °C and glass transition temperatures (Tg) up to 98 °C. Unfortunately, the incorporation of TADF moiety into these HBP materials induced non-TADF characteristics. However, when the HBPs functionalized as the host for our previously developed 4CzCNPy TADF dopant in solution processed devices, maximum external quantum efficiency of 5.7% and current efficiency of 17.9 cd/A have been achieved in P3-based device, which is significantly higher than those of 1.5% and 4.2 cd/A for the linear polymer P1.

Platinum complex was introduced in low ratios (0, 1, 1.5, and 5 mol%) as the third monomer in the conjugated backbone of well-known donor polymer PTB7-Th using a random terpolymer molecular design approach. All polymers showed similar absorption behavior and comparable HOMO/LUMO energy levels due to the small amount of Pt complex used. When blended with PC71BM in polymer solar cells, the power conversion efficiency was enhanced to 8.45% (obtained by the device based on PTB7-ThPt1.5 containing 1.5 mol% Pt) compared with 7.92% for the control PTB7-Th. Notably, the apparently low molecular weight of PTB7-ThPt1.5 (Mn/Mw: 46/70 kg mol−1) compared with that of PTB7-Th (Mn/Mw: 62/97 kg mol−1) ensured a more convincing comparison. Using a combination of physical measurements, such as optoelectrical characterization, grazing incident wide-angle X-ray diffraction (GIWAXS), and picosecond time-resolved photoluminescence, the efficiency enhancement was contributed by the higher hole mobility, less bimolecular recombination, and a more efficient slow charge separation process.

Donor-acceptor (D-A) type fully conjugated block copolymer systems have been rarely reported due to the challenges in synthetic approaches to prepare well-defined low-polydispersity products. In this work, fully conjugated block copolymers are synthesized in a one-pot reaction through Stille coupling polycondensation, by utilizing the end-functional polymer copolymerization method. End-functional P3HT are copolymerized with AA (2,7-dibromo-9-(heptadecan-9-yl)-9H-carbazole) and BB (4,7-bis(5-(trimethylstannyl)thiophen-2-yl)benzo[c][1,2,5]thiadiazole, TBT) type monomers, respectively. The orthogonal solubility between the very soluble P3HT donor and the insoluble PCDTBT acceptor block improves the purity of block copolymers as well as distinct nano-scale phase-separation compared with other reports on miscibility of donor and acceptor polymer block. Further purification via preparative GPC is carried out to remove the excess of unreacted P3HT and free PCDTBT as well as to achieve low polydispersity of block copolymers. The chemical structure of the P3HT-b-PCDTBT block copolymers are verified via 1H-NMR, and further confirmed by FTIR spectra. The block copolymer shows broad absorption and moderate optical band gap of 1.8 eV. Furthermore, the fully conjugated block copolymer films exhibit significant fine structures, much smoother film morphology compared to P3HT/PCDTBT polymer blends. By adding a small amount of block copolymer P3HT-b-PCDTBT as a compatibilizer into the bulk-heterojunction of P3HT:PC61BM blends, polymer solar cells with an 8% increase of short circuit current (J sc and 10% increase of power conversion efficiency (PCE) are achieved owing to the improvement of the active-layer film morphology. To the best of our knowledge, this is the first report on donor-acceptor type fully conjugated block copolymer as an effective ternary additive in polymer: fullerene bulk heterojunction solar cells.

The application of heavy-metal complexes in bulk-heterojunction (BHJ) solar cells is a promising new research field which has attracted increasing attention, due to their strong spin–orbit coupling for efficient singlet to triplet intersystem crossing. This review article focuses on recent advances of heavy metal complex containing organic and polymer materials as photovoltaic donors in BHJ solar cells. Platinum–acetylide containing oligomersor and polymers have been firstly illustrated due to the good solubility, square planar structure, as well as the fairly strong Pt–Pt interaction. Then the cyclometalated Pt or Ir complex containing conjugated oligomers and polymers are presented in which the triplet organometallic compounds are embedded into the organic/polymer backbone either through cyclometalated main ligand or the auxiliary ligand. Pure triplet small molecular cyclometalated Ir complex are also briefly introduced. Besides the chemical modification, physical doping of cyclometalated heavy metal complexes as additives into the photovoltaic active layers is finally demonstrated.

Direct (hetero) C–H arylation is an advantageous tool for the synthesis of diketopyrrolopyrrole (DPP) derivatives, because of fewer synthetic steps, better atom economy and being environmentally friendly. Herein, four diketopyrrolopyrrole containing linear structured D–A–π–A–D small molecules Ar(DPPT2)2 are facilely synthesized in high yields of 73–82% through C–H direct arylation, where Ar (from electron-donating 1,4-phenyl, 1,4-naphthyl or 9,10-anthryl to electron-accepting 2,5-pyridyl) is functionalized as the core π-bridge structure, DPP as the arm and bithiophene as end-groups. The dihedral angles between the central aryl rings and DPPT2 arms for the optimized geometries of Ph(DPPT2)2, NA(DPPT2)2 and AN(DPPT2)2 gradually increases from 20.3, 44.7 to 93.1°, respectively, which is 18.7° for the pyridyl cored Py(DPPT2)2. It is found that the optoelectronic properties can be elaborately tuned by variation of the central aryl bridge. Moreover, the coplanarity of the molecules as well as the electronic properties of central Ar units significantly affect the charge transport properties. Ph(DPPT2)2 possessing the best conjugated backbone planarity exhibits the highest hole mobility of 0.12 cm2 V−1 s−1 among the three Ar(DPPT2)2 compounds based on the electron-donating phenyl, naphthyl and anthryl cores, while the electron-withdrawing pyridyl core Py(DPPT2)2 shows a poor hole mobility of 6.47 × 10−4 cm2 V−1 s−1 despite of it having the most planar structure.

In order to improve the adsorption of heavy metal ions on acrylic hydrogels, P(AA-co-AM-co-S) hydrogels were synthesized from acrylic, acrylamide and styrene as raw materials. During the synthesis, potassium persulfate was used as the initiator, N, N’-methylenebisacrylamide was used as the crosslinking agent, and the degree of neutralization was 80%. The structure of the prepared hydrogel was determined by infrared spectroscopy. The adsorption properties of hydrogels on Ni2+ at different times and pH were determined. The results show that the adsorption capacity of Ni2+ ions on the hydrogel reaches the equilibrium adsorption capacity in about 2 hours and reaches 159 mg/g. The second-order kinetic model fits well. The optimal pH for the adsorption of Ni2+ ions by the hydrogel is 3.5 ~ 4.5 and the adsorption capacity is 160 mg/g. This study has important theoretical and practical significance for the development of high-efficiency, environmentally friendly, low-cost heavy metal ion hydrogels.

In the process of development, new media presents a completely different development mode from traditional media, namely, platform development mode. Under the effect of network effect, the new media platform can quickly gather a large number of users, and integrate the resources of all the endpoints on the platform through the platform operation, so that the information production becomes efficient and the phenomenon of collaborative production appears. The value of media platform development is mainly reflected in the construction of its bilateral economic model, and the key to the construction of the bilateral model lies in the transformation from the scale economy of the demand side to the scope economy of the supply side. This paper explores a service-oriented new media operation platform under the bilateral market economy mode, to construct a price structure for bilateral users, from the perspective of free mechanism, attention economy and supply side economies of scope. This new media operation platform can break the barriers of single information flow, build unlimited value-added services, promote the integration of information flow, capital flow and logistics platform, and thus create a service-oriented new media platform.

The incorporation of aggregation-induced emission (AIE) luminogens provides a molecule with enhanced fluorescent emission in the solid state. A representative AIEgen compound is tetraphenylethene (TPE). A series of new conjugates of quinolone derivatives with TPE units (1a - 1f) was synthesized and characterized. The influence on the photophysics of 1a - 1e with a variety of functional groups was investigated systematically by spectroscopic methods and simulated by density-functional theory calculations. A centrosymmetric compound donor-acceptor-donor-type compound 1f with two TPE moieties proved to be the most promising multifunctional material, it exhibited tri-colored (489–569 nm) fluorescence characteristics in tetrahydrofuran-H2O solution with a different water fraction and intense tri-colored solvatochromic (blue, green, and yellow) behaviors. These compounds could be applied as promising acid-base gas probe based on their evident color switch. Compounds 1a - 1f showed the advantage of being a potential piezochromic material.

In order to improve the adsorption of heavy metals in polyacrylic hydrogels, the experiment uses acrylic acid and styrene as raw materials, potassium per sulfate as initiator, and ethylene glycol as crosslinker to synthesize polyacrylic acid/styrene hydrogel. The effects of monomer ratio, acrylic acid neutralization degree, crosslinker dosage and temperature on product properties were studied by orthogonal test. In addition, the copolymer was characterized by fourier transform infrared spectroscopy. The adsorption of heavy metal performance test found that when the ratio of acrylic acid and styrene is 1:0.2, the degree of neutralization is 65%, the crosslinker accounts for 1.0% of the monomer mass fraction, and the temperature is 65 °C, the polyacrylic acid/styrene copolymer hydrogel is optimal. The adsorption of Pb2 + in the optimal group was 328.25 mg/g.

In this study, the linear high molecular weight polydimethylsiloxanes(PDMS) were synthesized by ultrasonic-assisted bulk ring-opening polymerization method, with D4 as the raw material, hexamethyldisilane(HMDS) as the capping agent and concentrated sulfuric acid as the catalyst. The mechanism of ring-opening polymerization assisted by ultrasound is discussed in detail, through the ultrasonic time, ultrasonic intensity and reaction temperature and other factors. The results showed that D4 ring-opening polymerization and PDMS depolymerization was a pair of reversible equilibrium reaction. Due to the influence of steric hindrance and viscosity, the ultrasonic action appears as the driving effect of D4 ring opening at the initial reaction, and the chain exchange or depolymerization of PDMS at the end of the reaction. Therefore, ultrasonic irradiation is believed to facilitate the rapid synthesis of high molecular weight PDMS at high monomer concentrations.

Fully conjugated donor-acceptor (D-A) block copolymers, P3HT-b-PNDIT, containing p-type poly(3-hexylthiophene) (P3HT) and n-type poly(naphthalene bismide) (PNDIT) segments are synthesized in a one-pot reaction via Stille coupling polycondensation. Various D-A block copolymers with low polydispersities (1.42–1.56) are obtained through further separation via preparative GPC. The structural and molecular features of block copolymers are verified by 1H NMR, FTIR spectra, UV-Vis absorption, differential scanning calorimetry (DSC) and cyclic voltammetry (CV). It is found that optical and electrochemical properties of D-A block copolymers are strongly dependent on the combination ratio of the donor P3HT and acceptor PNDIT segment. By reducing the acceptor block lengths, the highest occupied molecular orbital (HOMO) energy levels of D-A block copolymers sequentially rise, leading to the sequential decrease of energy gaps. To the best of our knowledge, this is the first report on engineering the energy levels of fully conjugated D-A block copolymers by tuning donor and acceptor chain lengths. More?over, compared to D/A polymer blends, the all-conjugated D-A block copolymer films show significant fine structures and much smoother film morphologies.