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Two novel adsorbents, triethylenetetramine-grafted hemp stems (HS-TETA) and choline chloride-grafted hemp stems (HS-CL), were prepared by using epichlorohydrin as etherifying agent. The obtained adsorbents were comprehensively characterized, and the adsorption capacity for hexavalent chromium (Cr(VI)) was evaluated under various single-factor conditions, including adsorbent dosage, contact time, solution pH, initial hexavalent chromium concentration, and temperature. HS-TETA and HS-CL exhibit excellent adsorption performance, with maximum adsorption capacities of 396.88 and 335.04 mg/g, respectively, outperforming previous relevant studies. The adsorption behavior of Cr(VI) by HS-TETA and HS-CL was investigated using adsorption kinetics, adsorption isotherms, and adsorption thermodynamics. The adsorption process follows the pseudo-second-order kinetic model and the Langmuir isotherm model, suggesting a monolayer adsorption process with chemical adsorption. Thermodynamic analysis reveals that the adsorption of Cr(VI) on two adsorbents is spontaneous and exothermic. Combined with the characterization, it can be speculated that the adsorption of Cr(VI) on two adsorbents involves electrostatic effects, reduction, and complexation processes. HS-TETA and HS-CL exhibit good recyclability. After 5 cycles, HS-TETA and HS-CL maintain over 50% and 85% of their initial adsorption capacity, respectively. The cycling performance of HS-CL containing quaternary ammonium and amine groups is significantly superior to that of HS-TETA containing only an amine group, indicating that the introduction of the quaternary ammonium group enhances the cycling performance of the adsorbent. HS-TETA and HS-CL, as cost-effective and efficient adsorbents, offer a promising solution for the treatment of Cr(VI)-contaminated wastewater and facilitate the recycling of agricultural waste. [Display omitted] • Two amino-modified hemp stem adsorption, HS-TETA and HS-CL, were synthesized. • The maximum adsorption capacity of HS-TETA for Cr(VI) reaches 396.88 mg/g. • The adsorption mechanism includes electrostatic, reduction, and complexation processes. • HS-TETA and HS-CL offer cost-effective solutions for Cr(VI) removal. [ABSTRACT FROM AUTHOR]

Porcine reproductive and respiratory syndrome (PRRS) remains one of the most economically significant diseases in the swine industry worldwide. The current vaccines are less satisfactory to confer protections from heterologous infections and long-term persistence, and the need for better vaccines are urgent. The immunological hallmarks in PRRSV-infected pigs include the unusually poor production of type I interferons (IFNs-α/β) and the aberrant and delayed adaptive immune responses, indicating that PRRSV has the ability to suppress both innate and adaptive immune responses in the host. Type I IFNs are the potent antiviral cytokines and recent studies reveal their pleiotropic functions in the priming of expansion and maturation of adaptive immunity. Thus, IFN antagonism-negative PRRSV is hypothesized to be attenuated and to build effective and broad- spectrum innate and adaptive immune responses in pigs. Such vaccines are promising alternatives to traditional vaccines for PRRSV. [ABSTRACT FROM AUTHOR]

[Display omitted] • Triethanolamine borate (TEOAB) was as efficient bifunctional catalyst for the cycloaddition of CO 2 with epoxides. • Most cyclic carbonates can be obtained in quantitative yields and high selectivity (99 %). • The catalyst can be easily separated from the product by water washing. Triethanolamine borate (TEOAB) possessing Lewis pair is an environmentally friendly, nontoxic, cheap and water-soluble catalyst for the cycloaddition of CO 2 with epoxides under solvent-free condition. Due to the synergistic effect of Lewis pair, TEOAB exhibits excellent catalytic activity and selectivity (99 %). The catalytic activity can be further improved by using TBAB as co-catalyst. Most cyclic carbonates can be obtained in quantitative yields and can be purified by water washing. [ABSTRACT FROM AUTHOR]

Background: Medicarpin is a natural pterocarpan-type phytoalexin widely distributed in many traditional Chinese medicines, such as Astragali Radix. A previous study showed that Astragali Radix demonstrated promising protective effects in neurons. However, there is no reported study on the neuroprotective function and the underlying mechanism of Medicarpin.Purpose: This study aimed to demonstrate the neuroprotective effect of Medicarpin on Alzheimer's disease (AD) and explore the therapeutic mechanisms.Method: First, we carried out animal behavioral tests and biochemical analysis to assess the anti-AD potential of Medicarpin for ameliorating spatial learning and memory and modulating cholinergic metabolism in scopolamine-induced amnesic mice. Subsequently, network proximity prediction was used to measure the network distance between the Medicarpin target network and AD-related endophenotype module. We identified Medicarpin-regulated AD pathological processes and highlighted the key disease targets via network analysis. Finally, experimental approaches including Nissl staining and Western blotting were conducted to validate our network-based findings.Result: In this study, we first observed that Medicarpin can ameliorate cognitive and memory dysfunction and significantly modulate cholinergic metabolism in scopolamine-induced amnesic mice. We then proposed an endophenotype network-based framework to comprehensively explore the AD therapeutic mechanisms of Medicarpin by integrating 25 AD-related endophenotype modules, gold-standard AD seed genes, an experimentally validated drug-target network of Medicarpin, and a global human protein-protein interactome. In silico prediction revealed that the effect of Medicarpin is highly relevant to neuronal apoptosis and synaptic plasticity, which was validated by experimental assays. Network analysis and Western blotting further identified two key targets, GSK-3β and MAPK14 (p38), in the AD-related protein regulatory network, which play key roles in the regulation of neuronal apoptosis and synaptic plasticity by Medicarpin.Conclusions: This study presented a powerful endophenotype network-based strategy to explore the mechanisms of action (MOAs) of new AD therapeutics, and first identified Medicarpin as a potential anti-AD candidate by targeting multiple pathways. [ABSTRACT FROM AUTHOR]

A new type of phosphine covalent organic frameworks (P-COFs) has garnered interest because of their high specific surface area and good thermal stability. These microporous materials have potential applications in gas storage, separation, heterogeneous catalysis, and other fields. Here, we present a heterogeneous catalyst consisting of a phosphine-based COF supported by palladium salt (Pd(OAc) 2 /P-COF) for Suzuki-Miyaura coupling reactions. The electron-rich heteroatoms (P, N) can securely anchor the active component (Pd) within the walls of P–COF. This catalyst exhibits excellent catalytic activity and cyclic stability. The coupling yield of phenylboronic acid and chlorobenzene with low activity reaches 100 % at room temperature for 3 h. After five cycles, the coupling yield of bromobenzene and phenylboronic acid remains above 93 %. [Display omitted] • A P–COF with a high specific surface area and suitable pore size distribution was successfully synthesized. • The electron-rich heteroatoms (P, N) within P–COF cananchor the active component, creating dispersed and stable catalytic sites. • Pd(OAc) 2 /P–COF exhibits outstanding activity and stability, enabling the conversion of various aryl halides into high yields. [ABSTRACT FROM AUTHOR]

Abstract: Single-crystalline SnO2 nanorods with large aspect ratios have been synthesized in poly (ethylene glycol) 200 (PEG-200) medium. The products are characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and high resolution transmission electron microscopy (HRTEM). The results indicate that the average diameter and length of the nanorods are 13nm and 550nm, respectively, presenting a mean aspect ratio of 42. These SnO2 nanorods show typical rutile phase and exhibit preferential growth along the [] direction. A proposed mechanism for the formation of SnO2 nanorods has also been discussed. In addition, photocatalytic activity study indicates that the as-prepared SnO2 nanorods present excellent photocatalytic degradation of Rhodamine B (RhB). When irradiated by a 300W high-pressure mercury lamp, the degradation of RhB reaches 100% within 45min. [Copyright &y& Elsevier]

Highly dispersed Pd nanoparticles immobilized in MIL-101 (Pd@MIL-101) were prepared and used for the catalytic dehydrogenation of Liquid organic hydrogen carriers (LOHC). The as-synthesized catalysts were characterized and it was found that 3 wt% of Pd@MIL-101 embodied smaller and highly dispersed Pd NPs. The catalytic activities of as-synthesized catalysts were investigated by the dehydrogenation of a representative LOHC compound, perhydro-N-propylcarbazole (12H-NPCZ). The results indicated that 3 wt% Pd@MIL-101 catalyst exhibited good catalytic activity and good reusability for the dehydrogenation of 12H-NPCZ, which is superior to that of commercial 5 wt% Pd/Al 2 O 3 catalyst. This study demonstrates that Pd@MIL-101 is a promising dehydrogenation catalyst for the application of LOHC technology. Image 1 • Highly dispersed Pd NPs immobilized in MIL-101 (Pd@MIL-101) were prepared. • 3 wt% catalyst exhibits better catalytic activity than commercial 5 wt% Pd/Al 2 O 3. • Pd@MIL-101 shows good reusability for the catalytic dehydrogenation of 12H-NPCZ. [ABSTRACT FROM AUTHOR]

Abstracts We report a new candidate of liquid organic hydrogen carrier, 1-methylindole, with a hydrogen content of 5.76 wt% and a low melting point of below −20 °C. The hydrogenation of 1-methylindole and the dehydrogenation of octahydro-1-methylindole were investigated in details. Full hydrogenation of 1-methylindole was realized over a 5 wt% Ru/Al 2 O 3 catalyst at 130 °C and 6.0 MPa, and both conversion and selectivity of 100% towards octahydro-1-methylindole were achieved. The catalytic dehydrogenation of octahydro-1-methylindole was carried out over a 5 wt% Pd/Al 2 O 3 catalyst. By using a combined experimental and density functional theory approach, the mechanism of octahydro-1-methylindole dehydrogenation to 1-methylindole and the two stable isomers of octahydro-1-methylindole were analyzed. The effect of reaction temperature and dosage of catalyst on the hydrogen release content were systematically studied. In addition, the dehydrogenation of octahydro-1-methylindole at 160–190 °C on Pd/Al 2 O 3 was well described by a first-order stepwise dehydrogenation reaction with the apparent activation energy of 122.99 kJ/mol. The purity of released H 2 was higher than 99.99% with no detectable impurity. [ABSTRACT FROM AUTHOR]

A solid Zn Complex (Zn(HBA) 2) with o -Hydroxybenzyl-Amine, which can be easily prepared by a one-step synthesis method, was exploited for the CO 2 transformation to cyclic carbonates. The results demonstrated that Zn(HBA) 2 is a high-efficiency catalyst in the coupling reaction between CO 2 and epoxides under solvent-free conditions. Under mild conditions (80 °C, atmospheric CO 2), epoxides with different substituents have been successfully transformed into the relevant cyclic carbonates with high yields and selectivity (>99%). The turnover frequency (TOF) was reached to 21,667 h−1 for the coupling of CO 2 and epichlorohydrin (ECH) into chloropropene carbonate (CPC) under 120 °C and a 1.8 MPa of CO 2 pressure within 3 h. This catalyst is capable of recovering and reusing by simple filtration. The catalytic mechanism of Zn(HBA) 2 for the cycloaddition reaction was proposed. A solid Zn Complex acts as heterogeneous catalyst for the coupling of CO 2 and epoxides without solvent at mild conditions. The catalyst can be recovered and reused by a simple filtration. [Display omitted] • A solid Zn Complex (Zn(HBA) 2) was synthesized by one-step synthesis method. • A series of epoxides have been converted into the corresponding cyclic carbonates in high yields at mild conditions. • The TOF of 21,667 h−1 was achieved for the conversion of CO 2 with epichlorohydrin into cyclic carbonate. • Zn(HBA) 2 can be recovered and reused by a simple filtration without obvious loss of its catalytic activity after five cycles. [ABSTRACT FROM AUTHOR]

Hydrogenation of N-ethylindole was investigated over a 5 wt% Ru/Al 2 O 3 catalyst in the temperature range of 160–190 °C at 9 MPa. The process was found to undergo the sequential steps of N-ethylindole → 2H-N-ethylindole → 4H-N-ethylindole → 8H-N-ethylindole with rapid consumption of all intermediate species. The reverse process, dehydrogenation of octahydro-N-ethylindole, was subsequently conducted for tests over a 5 wt% Pd/Al 2 O 3 catalyst in the same temperature range. Full dehydrogenation can be achieved with a moderate reaction rate. The released H 2 gas was found to be of a high purity. Our results indicate that N-ethylindole is a promising new member of liquid organic hydrogen carrier family. [ABSTRACT FROM AUTHOR]

N-ethylcarbazole is one of the most promising liquid organic hydrogen carriers (LOHCs) as it can be catalytically hydrogenated and dehydrogenated at relatively moderate temperatures. In the present work, we report a systematic study on dehydrogenation of perhydro-N-ethylcarbazole over several important supported noble metal catalysts to identify the optimal catalyst for temperature-controlled dehydrogenation. The reaction takes three consecutive stages with two intermediates of octahydro-N-ethylcarbazole and tetrahydro-N-ethylcarbazole. The initial catalytic activity of the selected noble metal catalysts for the dehydrogenation process was found to follow the order of Pd > Pt > Ru > Rh. 100% selectivity toward the final product of N-ethylcarbazole and fully dehydrogenation was achieved over the supported Pt and Pd catalysts. The kinetics of the three stage dehydrogenation processes over the catalysts was studied and the rate constants were derived. The results indicate that the dehydrogenation reaction rate decreases significantly with the reaction stage for all the selected noble catalysts and the conversion from tetrahydro-N-ethylcarbazole to N-ethylcarbazole was found to be the rate-limiting step of the entire reaction process. [ABSTRACT FROM AUTHOR]

The efficient capture of nuclear waste such as radionuclide iodine has received more worldwide attention because of the effects of radiation on biological health. Adsorption is considered to be an efficient, low-cost, and environmentally friendly method for iodine removal. Recently, a new kind of phosphine-based covalent organic frameworks (P-COFs) with flexible and nonplanar structure have attracted great attention because of their high specific surface area and good thermal stability. The existence of electron-rich heteroatoms (P, N) as well as the large π-conjugated network structure may be beneficial to the absorption of iodine. In this study, a biphenyl linked P-COF was synthesized for the capture of iodine. It shows a uniform microsphere structure with a diameter of about 1.2 μm, a large BET surface area up to 1056 m2 g−1, and a high thermal stability (up to 500 °C). This P-COF exhibits rapid and exceptional iodine uptake in both volatile iodine and iodine/cyclohexane solution with adsorption capacities of 6.19 g g−1 and 1.30 g g−1, respectively, suggesting that P-COF may be a potential candidate for radioiodine capture from nuclear waste. [Display omitted] • A phosphine-based covalent organic framework (P-COF) is developed for the capture of iodine. • P-COF exhibits rapid volatile iodine uptake with an adsorption capacity of 5.00 g g−1 within 2 h. • The equilibrium adsorption capacity of vapor iodine reaches as high as 6.19 g g−1. • P-COF shows tremendous iodine adsorption with capacity of 1.30 g g−1 in cyclohexane solution. [ABSTRACT FROM AUTHOR]

Nuclear waste such as radioactive iodine has been received worldwide attention because of the effects of radiation on biological health. The efficient capture of radioactive iodine is of great importance for the safe utilization of nuclear energy. In this study, a functional porous organic polymer (P-TzTz) with high sulfur and nitrogen contents was synthesized by the catalyst-free hydrothermal process of dithiocarbanate (DTO) and benzo[1,2-b:3,4-b′:5,6-b″]trithiophene-2,5,8-tricarbaldehyde (BTT-THO) in N , N -dimethylformamide under N 2 atmosphere. This tailor-made amorphous polymer exhibits high affinity and adsorption capacity for iodine owing to its effective electron-rich sorption sites, π-conjugated structure and hierarchically porous structure. P-TzTz displays an excellent reversible iodine uptake with capacity of 326 wt% for volatile iodine. After five cycles of volatile iodine adsorption, P-TzTz almost retains the same adsorption capacity with the original adsorbent. In addition, P-TzTz also exhibits excellent adsorptive performance for the removal of iodine from iodine/cyclohexane solution with an adsorption capacity of 494.09 mg g−1, suggesting that P-TzTz may be also an effective adsorbent for the removal of iodine from solution. Image 1 • A functional porous organic polymer with rich S and N (P-TzTz) was synthesized. • P-TzTz shows excellent volatile iodine uptake of 326 wt%. • P-TzTz can adsorb iodine in cyclohexane solution with an excellent adsorption capacity of 494.09 mg g−1. • After five cycles, P-TzTz shows almost the same iodine adsorption capacity with pristine. [ABSTRACT FROM AUTHOR]

Organic dye containing wastewater and nuclear waste have received more worldwide attention because of the significant environmental problems and the effects of radiation on health. Adsorption is considered to be an efficient, low-cost, and environmentally friendly method for pollutant removal. In this paper, we developed a novel covalent organic framework (BTT-TAPT-COF) adsorbent which contains abundant S and N active sites as well as extended π-conjugated structure. This COF shows high crystallinity, large surface area, and thermal stability. Due to the porous feature, existence of electron-rich heteroatoms as well as the large π-conjugated network structure, BTT-TAPT-COF exhibits excellent adsorptive performance for the removal of hazardous dye indigo carmine with an adsorption capacity of 547.33 mg g−1 and rapid reversible volatile iodine uptake with an adsorption capacity of 276 wt%. After five cycles, BTT-TAPT-COF almost retains the same iodine adsorption capacity with the original adsorbent. Image 1 • N- and S-rich covalent organic framework (BTT-TAPT-COF) was synthesized. • The BTT-TAPT-COF absorbs hazardous dye indigo carmine with an excellent adsorption capacity of 547.33 mg g−1. • BTT-TAPT-COF shows the iodine uptake of 276 wt%. • BTT-TAPT-COF retains almost the same iodine adsorption capacity with the original adsorbent. [ABSTRACT FROM AUTHOR]