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Combing carboxylic acid-functionalized carbon nanotubes with triazine-based covalent organic frameworks for supercapacitor electrode materials with high specific capacitance performance.

The structure diagram of SFN-CTFs and the cycle diagram of SFN-CTF(1 : 2)-1 are presented.

Integrating modified θ-Al2O3 and triazine-based covalent organic framework composites for electrode materials in supercapacitors with enhanced specific capacitance performance.

This paper studies the disciplinary spillover effects of proxy contests on companies that share directors with target firms, that is, interlocked firms. In difference-in-differences tests, I find that interlocked firms reduce excess cash holdings, increase shareholder payouts, cut CEO compensation, and engage in less earnings management in the year after proxy contests. The effects are more pronounced when both the interlocked and target firms have a unitary board and when the interlocking director is up for election, is younger, or has shorter tenure. Overall, the evidence highlights the importance of directors’ career concerns in policy spillovers across firms with board interlocks.

By selecting the building blocks with different active sites, 4-formylphenylboronic acid (FBA), 3,3′,5,5′-tetrabromo-2,2′-benzothiophene (DDT) and N,N′,N′′,N′′′-tetra(p-phenylene)para-phenylenediamine (TABD), two conjugated microporous polymers (CMPs), SNCMP-1 and SNCMP-2, with multiple active sites were synthesized via a palladium(II)-catalyzed coupling reaction. They exhibited excellent performances in volatile iodine capture with iodine adsorption values of 570 and 698 wt%, respectively. In addition, SNCMP-1 and SNCMP-2 displayed outstanding CO2 adsorption capacities with uptakes up to 3894 and 3878 mg g−1 at 70 bar and 323 K conditions, respectively.

A novel 3D MOF [(Zn4O)(H2O)2(TPA)2]·8DMA (1) (H3TPA = 4,4′,4′′-nitrilotrisbenzoic acid; DMA = N,N-dimethylacetamide) with tetragonal nanochannels has been rationally obtained under solvothermal conditions using the fluorescent ligand H3TPA. MOF 1 demonstrates a unique (3,6)-connected network with nanosized square channels, displaying strong blue emission. Interestingly, 1 can be used as a fluorescent probe, which can detect nitroaromatic explosives efficiently and selectively via fluorescence quenching phenomena. As the number of –NO2 groups increase, fluorescence quenching becomes more obvious, which is maybe because the energy transfer from the electron-donating framework to electron-withdrawing nitroaromatic analytes becomes greater. Notably, the sensor is particularly sensitive to picric acid (PA), showing complete fluorescence quenching at a PA concentration as low as 30 ppm. MOF 1 can be recycled in the detection of nitroaromatic explosives with excellent recyclability. Additionally, the photo-induced electron transfer mechanism was validated through theoretical calculations for the fluorescence quenching.

A red luminescent europium ion (Eu3+) doped CMP composite (Phen-Eu@BPPD-CMP) was prepared for the first time, in which Eu3+ ions coordinated with diketone moieties and 1,10-phenanthroline (Phen). The fluorescent composite could be used as a chemosensor for highly sensitive and selective detection of aluminum ions (Al3+). Compared to a linear polymer analogue (Phen-Eu@BPPD-LP), Eu3+-doped CMP without Phen groups (Eu@BPPD-CMP), and a Eu(OAc)3-BPPD-CMP mixture, Phen-Eu@BPPD-CMP allowed for the rapid detection of Al3+, which could have been caused by the mutual promotion of π-conjugated skeletons and the complementary coordination of Phen groups to facilitate the sensing process and improve the response to Al3+ ions.

The likelihood of seasoned equity offerings (SEOs) jumps discontinuously when the stock price equals the most recent equity offer price. Anchoring on the last offer price holds after considering executive turnovers, stock splits, earnings management, or dividend adjustments. Using a fuzzy regression discontinuity design around this cutoff, which exploits local randomness in stock prices, we investigate the consequences of anchoring in SEOs. We find significant increases in cash holdings and acquisitions of lower quality, with no real effects on investment or employment. Overall, we provide some of the cleanest estimates, to date, of the timing and causal effects of SEOs.

Herein, we present a rational strategy for the development of π-electron-enriched conjugated microporous polymers (CMPs) under mild conditions, aiming for the super-adsorption of iodine. Among them, TBTT-CMP@1 exhibits a superior iodine uptake up to 442 wt%. In addition, TBTT-CMP@3 displays outstanding CO2 adsorption capacity with uptake up to 1578 mg g−1 under 70 bar and 318 K conditions.

We present three novel conjugated microporous polymers (CMP@1–3), which were formed by an imidization reaction between tetra-(4-aminophenyl)ethylene and anhydrides. These CMPs exhibited high CO2 and organic vapor capture capacity.

Porous cationic covalent triazine-based frameworks (CTFs) with imidazolium salts as tectons were prepared via ionothermal synthesis. The high-PF6 - -content CTF shows the CO2 adsorption of 44.7 cm3 g-1 and I2 capture capacity of 312 wt %. The influence of counterion species and contents on the porosities, CO2 adsorptions, and I2 capture capacities of the CTFs has been investigated.

The fluorine chemical industry has become an important one with rapid development because of its large variety of products, excellent performance and wide application fields. However, the hypertoxic materials which widely exist in fluorochemical engineering processes make the safety management and reliability assessment especially important. To improve the monitoring performance of the complicated fluorochemical engineering processes, an online Hidden Markov Model based method was proposed to predict the system reliability in real time. In this paper, the variables highly related to the system reliability were used as inputs for the unsupervised clustering method to classify the process states into different categories. Then they were used as the observable states to train the Hidden Markov Model with the system reliability as the hidden state. The superiority of the proposed method in estimating system reliability for the complicated fluorochemical engineering process has been strongly proved by the application on the R-22 fluorochemical engineering process. Moreover, the application on Tennessee Eastman process also confirmed its generalization performance for other complicated black-box chemical processes.

The evolutionarily conserved lethal-7 (let-7) microRNAs (miRNAs) are well-known activators of proliferative quiescence and terminal differentiation. However, in the murine auditory organ, let-7g overexpression delays the differentiation of mechano-sensory hair cells (HCs). To address whether the role of let-7 in auditory-sensory differentiation is conserved among vertebrates, we manipulated let-7 levels within the chicken auditory organ: the basilar papilla. Using a let-7 sponge construct to sequester let-7 miRNAs, we found that endogenous let-7 miRNAs are essential for limiting the self-renewal of HC progenitor cells. Furthermore, let-7b overexpression experiments revealed that, similar to mice, higher than normal let-7 levels slow/delay HC differentiation. Finally, we identify CHD7, a chromatin remodeler, as a candidate for mediating the repressive function of let-7 in HC differentiation and inner ear morphogenesis. Our analysis uncovered an evolutionarily conserved let-7-5p-binding site within the chicken Chd7 gene and its human and murine homologs, and we show that let-7g overexpression in mice limits CHD7 expression in the developing inner ear, retina and brain. Haploinsufficiency of CHD7 in humans causes CHARGE syndrome and attenuation of let-7 function may be an effective method for treating CHD7 deficiency.

Reductive soil disinfestation (RSD) is an effective agricultural practice to eliminate soil-borne pathogens that heavily relies on the organic substrate used. However, the influences of combined application of organic residues on disinfestation efficiency, soil microbiomes, and their associated functional characteristics are still not well-characterized. In this work, four treatments, i.e., untreated soil (CK), RSD with 15 t ha-1 sugarcane bagasse (SB), bean dregs (BD), and their combinations (1:1, SB+BD), were conducted to investigate their influence on disinfestation efficiency, microbial functional diversity, community diversity, and composition using Biolog analysis, real-time PCR, and high-throughput sequencing. The SB+BD treatment had synergetic effects on soil microbial activity, metabolic activity, and functional diversity with similar efficacy in pathogen elimination and soil salinization alleviation, as compared to the SB and BD treatments. Moreover, the SB+BD treatment distinctly altered the structure and composition of bacterial and fungal communities, especially enriched the core microbiomes associated with soil general functions such as organic decomposition and nitrate removal. The SB+BD treatment also strengthened the soil specific functions including disease suppression through the regulation of unique microbiomes. In addition, the microbial richness, diversity, and evenness were significantly higher in the SB+BD-treated soil as compared to the SB- and BD-treated soils. Taken together, RSD incorporated with organic residue combination not only efficiently restore the degraded soils, but also considerably improve soil functions, which may benefit to the health for the future plant generations. KEY POINTS: • Organic residue combination effectively declines pathogen density. • Organic residue combination improves soil microbial activity and functional diversity. • The enriched core microbiome is responsible for soil general functions. • The induced unique microbiome is important for soil specific functions.

The enrichment of radioactive iodine in the waste of nuclear industries threatens human health, and thus the efficient capture of iodine has attracted a great deal of attention in recent years. Porous organic polymers (POPs) and metal–organic frameworks (MOFs), new classes of porous materials, act as outstanding candidate adsorbent materials in this field due to their high surface areas, permanent tunable porosities, controllable structures, high thermal/chemical stabilities, versatility in molecular design and potential for post-synthetic modification. Herein, this review focuses on the research progress of these two types of porous materials for highly efficient iodine capture. We analyze and discuss some valid strategies for enhancing their iodine uptake, including increasing their surface area and pore volume, using organic building units with unique configurations and functions, introducing chemical functional groups to provide high-enthalpy binding sites, and further processing of POP and MOF materials. Indeed, there are many special structural and functional features found in porous POP and MOF materials, which make them unique and merit further exploration. Thus, we expect to see their usage grow as this field progresses.

Herein we present a rational strategy for the design of a porous organic structure based on conjugated microporous polymers (CMPs), aiming for the super absorption of CO2. The porous skeleton netted with thiophene- and carbazole- polar building blocks exhibits a synergistic effect on the absorption of CO2; the polar moiety facilitates the interaction between CO2 and the porous materials, and the high surface area provides a large interface. Among them, the task specific copolymer SN@CMP-6, exhibits a superior CO2 uptake at 1.05 bar and 273 K (86.46 cm3 g−1). All of the copolymers show high isosteric heats of CO2 adsorption (38.6–59.8 kJ mol−1).

We present two novel porphyrin (Porp)-based conjugated microporous polymers (CMPs; Porp-TPE-CMP and Porp-Py-CMP), formed via an FeCl3-catalyzed cross-coupling reaction between pyrrole and aromatic aldehyde. The resultant CMPs exhibited high CO2 selectivity compared with N2 and CH4, and good capacity for organic vapors.

A copper porphyrin-based conjugated microporous polymer (CuPs-CMP@72 h, SBET = 1240 m2 g−1) was synthesized, characterized, and further applied as a promising photocatalyst in the oxidation reaction of 1,3-diphenyllisobenzofuran to 1, 2-phenylene-bis(phenylmethanone). Furthermore, the effect of metal atom and porosity of the CMP network play an important role on generating the singlet oxygen.

By modulating the reaction pH value, two new CoII compounds, [Co2(L)(biz)(OH)]·H2O (JLNU-5) and [Co(HL)(biz)] (JLNU-6) (H3L = 5-(4-carboxybenzyloxy)isophthalic acid, biz = benzimidazole, JLNU = Jilin Normal University), have been successfully synthesized under mild hydrothermal conditions. JLNU-5 displays a 2D layer 4-connected sql topolygy. JLNU-6 is a 2D sheet structure and (3,6)-connected net with (43)(46 · 66 · 83) topology. In addition, the magnetic property of JLNU-5 and JLNU-6 is investigated, which shows the antiferromagnetic behavior induced by the external field.

The products and services of firms operating in sin industries (alcohol, tobacco, gambling, and firearms) run contrary to social norms and can produce significant negative externalities for society. As such, we expect that sin firms are at greater risk of incurring political costs in the form of additional regulation, higher excise taxes, or capital market intervention if they come under scrutiny for their income tax avoidance practices. Because of the nature of their products, regulators and policymakers are likely to face less pushback on new regulations or taxes on these firms. Sin firms start with a lower ability to influence the political process than firms in non-sin industries. Consequently, we hypothesize and find that sin firms exhibit less tax avoidance than non-sin firms, particularly through uncertain and more risky tax avoidance strategies. The negative relationship between the status of sin firms and tax avoidance is less pronounced in firms that accumulate political capital via intensive lobbying activities. Exploiting changes in partisan control of the Congress and White House, difference-in-differences tests show that firearm firms engage in less (more) tax avoidance when the Democrats (Republican) control both the Congress and White House. Overall, we conclude that political costs play an important role in corporate tax avoidance decisions.

A new stable Cd(II)-MOF [Cd(PBA)(pic)(H2O)]·H2O·0.5DMA (1) (HPBA = 4-(pyridin-4-yl) benzoic acid, Hpic = 2-picolinic acid, DMA = N, N'-dimethylacetamide) has been successfully constructed by solvothermal condition and characterized in detail. MOF 1 exhibits excellent chemical stability in water, which provides possible for sensing in water. The luminescent spectra demonstrate different to different metal cations. Notably, Fe3+ causes the highest fluorescence quenching, and the quenching efficiency is up to 96% at a concentration of 10−3 M Fe3+ in aqueous solution. Additionally, there was no obvious change in fluorescent quenching efficiency after 5 sensing cycles. Therefore, MOF 1 is expected to be used as a fluorescent probe for sensing Fe3+ in water with high selectivity, sensitivity, and recyclability.

A porphyrin-based two-dimensional covalent organic framework (TPE-Por-COF) with high stability was synthesized, and the adsorption performance of TPE-Por-COF on organic dyes was studied. The TPE-Por-COF was characterized by X-ray powder diffraction, infrared spectroscopy, solid-state nuclear magnetic resonance, thermogravimetry and N2 adsorption isotherms. TPE-Por-COF has adsorption effect on five dyes: malachite green (MG), methyl violet (MV) and rhodamine B (RhB), coomassie brilliant blue (CBB) and brilliant green (BG). Among them, TPE-Por-COF has the most obvious adsorption effect on malachite green, and the adsorption capacity is as high as 1428.57 ​mg ​g-1. In addition, the CO2 adsorption capacity of TPE-Por-COF is 187 ​mg ​g-1 at 50 ​bar and 323 ​K.

The adsorption of iodine by porous organic polymers is an active research topic. Two new thiol-linked conjugated microporous polymers (SHCMPs) were successfully prepared by thioalkynes click polymerization. Lone pair electrons of heteroatoms can enhance the interaction between adsorbent and adsorbate, the ability of adsorbent to capture iodine can be improved by introducing electron-rich groups such as nitrogen, thiophene, fluorine, etc. The saturated iodine adsorption capacities of SHCMP-1 and SHCMP-2 are 590 and 495 wt.%, respectively. In addition, SHCMP-2 performs well in detecting Fe3+ in aqueous solution, which has potential importance for industrial application of water treatment.

Covalent triazine skeletons (CTFs) are long-chain polymers with rigid hydrophobic aromatic skeletons and polar functional groups. Here, we selected three monomers to explore a series of stable CTFs (FCTFs, NCTFs, ClCTFs) with multiple active sites at 350 and 400 °C respectively, which can act as a porous platform for effective and reversible iodine capture. The iodine adsorption capacities of FCTF@350, NCTF@350, ClCTF@350, FCTF@400, NCTF@400 and ClCTF@400 are 285, 232, 231, 382, 372 and 340 wt%, respectively. Among them, the iodine capture capacities of FCTFs and NCTFs are higher than those of ClCTFs, which suggested that the introduction of electron-rich F and pyridine N groups can indeed improve the iodine adsorption capacity of the polymers. In addition, at 50 bar and 323 K, the CO2 capture capacity of FCTF@350, NCTF@350, ClCTF@350, FCTF@400, NCTF@400 and ClCTF@400 are 631.6, 539.2, 496.6, 876.6, 783.3, and 695.4 mg g−1, respectively. This shows that polymers have good applications in CO2 capture.

Porous cationic covalent triazine-based frameworks (CTFs) with imidazolium salts as tectons were prepared via ionothermal synthesis. The high-PF

Marathon running has become an obsession in China, with 22 marathon races in 2011 increasing to 400 in 2017. Based on the Marathon annual report in 2017, marathon races will increase to above 1900 in 2020. More and more Chinese are traveling around the country to participate marathon races, which brings tremendous opportunities for the host cities, specifically for city tourism. A well-designed marathon map can not only help runners to learn detailed information for the races, but also help the tourists to learn natural and historical spots in the city. However, marathon maps and their designs are not examined in respect to cartography.This study focused on full marathon race maps, collected 200 maps officially published by marathon organizers, inventoried the race information included in the maps, explored how many of these maps showing natural and historical scenic spots along the race, and analyzed common design elements of the maps using Quantitative Content Analysis (QCA), see table1. The goal of this study was to determine if the maps featured only the races or if they provided additional information to encourage tourist activities. A well designed marathon map can help both to the implementation of a race and to the creation of a sense of city.