Abstract
Herein, a facile and general electroreductive deuteration of unactivated alkyl halides (X = Cl, Br, I) or pseudo-halides (X = OMs) using D
2
O as the economical deuterium source was ...reported. In addition to primary and secondary alkyl halides, sterically hindered tertiary chlorides also work very well, affording the target deuterodehalogenated products with excellent efficiency and deuterium incorporation. More than 60 examples are provided, including late-stage dehalogenative deuteration of natural products, pharmaceuticals, and their derivatives, all with excellent deuterium incorporation (up to 99% D), demonstrating the potential utility of the developed method in organic synthesis. Furthermore, the method does not require external catalysts and tolerates high current, showing possible use in industrial applications.
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•Carboxyl functionalized Ti3C2Tx MXene (TCCH) was synthesized.•The stability of the TCCH in water was significantly improved compared with raw Ti3C2Tx.•The optimized TCCH showed ...superior U(VI) and Eu(III) adsorption capacities up to 334.8 mg/g and 97.1 mg/g, respectively.•The adsorption mechanism was associated with inner-sphere surface complexation and electrostatic interaction.
With the development of nuclear power, the negative environmental impact such as radioactive pollution has become an urgent issue to impede the utilization of nuclear energy. The construction of promising organic-inorganic hybrid materials is considered as an effective strategy for environmental remediation of radioactive contamination. In this work, two-dimensional transition metal carbide (MXene), an emerging inorganic layered material, has been successfully modified by carboxyl terminated aryl diazonium salt to both enhance its chelating ability to radionuclides and improve its water stability. The carboxyl functionalized Ti3C2Tx MXene (TCCH) shows excellent removal ability for U(VI) and Eu(III), evidenced by ultrafast adsorption kinetics (3 min), high maximum adsorption capacities (344.8 mg/g for U and 97.1 mg/g for Eu) and high removal percentage of radionuclides from artificial groundwater (> 90%). The adsorption of U(VI) and Eu(III) on TCCH are in good accord with the Langmuir adsorption isotherm model and the pseudo-second-order kinetic model. Ionic strength experiments, X-ray photoelectron spectroscopy (XPS) and Extended X-ray absorption fine structure (EXAFS) analyses were conducted to assess the detailed adsorption mechanism. The results reveal that the adsorption of U(VI) on TCCH follows an inner-sphere configuration, whereas the adsorption of Eu(III) is determined by both inner-sphere complexation and electrostatic interaction.
Trauma memorials that preserve painful memories use the display of trauma to combine the memories and feelings of individuals, society, ethnic groups, and countries into a force that keeps the ...histories of victims from being lost and also makes visitors understand their own social moral responsibility and contemplate their attitude toward the future. This paper therefore uses the examples of memorial museums for "comfort women" 慰安婦 in East Asian society, including the Nanjing Museum of the Site of the Lijixiang Comfort Stations 南京利濟巷慰安所舊址陳列館, Chinese Comfort Women History Museum "慰安婦"歷史博物館, Taiwan Ama Museum for Peace and Women's Human Rights 阿嬷家：和平與女性人權館, South Korean War and Women's Human Rights Museum 戰爭與女性人權博物館, and Japanese Women's Active Museum on War and Peace 女性戰爭與和平資料館 to discuss how trauma narratives are made and how trauma memorials should construct collective memories and assume social responsibility.
The DABB proteins, which are characterized by stress-responsive dimeric A/B barrel domains, have multiple functions in plant biology. In Arabidopsis thaliana, these proteins play a crucial role in ...defending against various pathogenic fungi. However, the specific roles of DABB proteins in Brassica napus remain elusive. In this study, 16 DABB encoding genes were identified, distributed across 10 chromosomes of the B. napus genome, which were classified into 5 branches based on phylogenetic analysis. Genes within the same branch exhibited similar structural domains, conserved motifs, and three-dimensional structures, indicative of the conservation of BnaDABB genes (BnaDABBs). Furthermore, the enrichment of numerous cis-acting elements in hormone induction and light response were revealed in the promoters of BnaDABBs. Expression pattern analysis demonstrated the involvement of BnaDABBs, not only in the organ development of B. napus but also in response to abiotic stresses and Sclerotinia sclerotiorum infection. Altogether, these findings imply the significant impacts of BnaDABBs on plant growth and development, as well as stress responses.
Cationic spherical polyelectrolyte brushes (SPBs) were synthesized by photoemulsion polymerization, consisting of a polystyrene core with a diameter around 80 nm and a poly(2-aminoethylmethacrylate ...hydrochloride) (PAEMH) shell with a thickness from 10 to 50 nm densely grafted on the core surface. The binding of various proteins onto SPBs was observed by turbidimetric titration, dynamic light scattering (DLS), zeta potential, and isothermal titration calorimetry (ITC). The binding, aggregation, and releasing of proteins by SPB can be tuned by modulating pH. The pH regions of binding for bovine serum albumin (BSA), β-lactoglobulin (BLG), and papain onto SPBs are markedly different and tunable by ionic strength and stoichiometry between protein and SPB. Binding energetics, affinity, and amount of various proteins onto cationic SPBs were determined by ITC. These findings lay the foundation for SPB applications in the protein purification and selective immobilization of different proteins, enzymes, and antibodies.
In this paper, we use the properties of Chebyshev polynomials, elementary methods, and combinational techniques to study the computational problem of one kind of convolution sums involving second ...kind Chebyshev polynomials, and we give an exact computational method, which expresses the sums as second kind Chebyshev polynomials. As some applications of our results, we also obtain several new identities and congruences involving the second kind Chebyshev polynomials, Fibonacci numbers, and Lucas numbers.
Abstract
In this paper, we propose an efficient quantum carry-lookahead adder based on the higher radix structure. For the addition of two
n
-bit numbers, our adder uses
$$O(n)-O(\frac{n}{r})$$
O
(
n
...)
-
O
(
n
r
)
qubits and
$$O(n)+O(\frac{n}{r})$$
O
(
n
)
+
O
(
n
r
)
T gates to get the correct answer in T-depth
$$O(r)+O(\log {\frac{n}{r}})$$
O
(
r
)
+
O
(
log
n
r
)
, where
r
is the radix. Quantum carry-lookahead adder has already attracted some attention because of its low T-depth. Our work further reduces the overall cost by introducing a higher radix layer. By analyzing the performance in T-depth, T-count, and qubit count, it is shown that the proposed adder is superior to existing quantum carry-lookahead adders. Even compared to the Draper out-of-place adder which is very compact and efficient, our adder is still better in terms of T-count.
Molecular communications via diffusion (MCvD) represents a relatively new area of wireless data transfer with especially attractive characteristics for nanoscale applications. Due to the nature of ...diffusive propagation, one of the key challenges is to mitigate inter-symbol interference (ISI) that results from the long tail of channel response. Traditional coherent detectors rely on accurate channel estimations and incur a high computational complexity. Both of these constraints make coherent detection unrealistic for MCvD systems. In this paper, we propose a low-complexity and noncoherent signal detector, which exploits essentially the local convexity of the diffusive channel response. A threshold estimation mechanism is proposed to detect signals blindly, which can also adapt to channel variations. Compared to other noncoherent detectors, the proposed algorithm is capable of operating at high data rates and suppressing ISI from a large number of previous symbols. Numerical results demonstrate that not only is the ISI effectively suppressed, but the complexity is also reduced by only requiring summation operations. As a result, the proposed noncoherent scheme will provide the necessary potential to low-complexity molecular communications, especially for nanoscale applications with a limited computation and energy budget.
Radioactive strontium 90Sr with a half-life of 29 years is one of the most concerned elements in both nuclear accidents and spent fuel reprocessing. Herein, using macroporous silica SiO2 as support, ...methylacrylic acid as functional monomer and ethylene glycol dimethacrylate as cross-linking agent, a novel resin named SiMaC was prepared via in situ polymerization method for strontium removal. The as-preapred SiMaC was characterized by SEM-EDS, TG-DSC, and BET. Various factors such as pH, m/V, time, and initial concentration of Sr(II) were studied. The maximum adsorption capacity towards Sr(II) was as high as 142.5 mg/g at 298 K. The adsorption equilibrium was almost obtained within 30 min. Moreover, SiMaC was easily and fastly regenerated by 0.1 M HCl and exhibited no obvious decrease in adsorption capacity after five times of successive adsorption-desorption cycles. Most attractively, the uptake rate of Sr(II) reached more than 99% in real river and lake water mediums, as well as reached 76% in real seawater mediums. Finally, XPS and FTIR were used to analyze the adsorption mechanism towards Sr(II).
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•A carboxyl functionalized resin SiMaC was prepared via in situ polymerization.•The adsorption isotherm, kinetics, and thermodynamics of Sr on SiMaC were explored.•SiMaC exhibited a maximum adsorption capacity of 142.5 mg/g towards Sr(II).•The uptake rate of Sr in river water, lake water and sea water are 99%, 99% and 76%.•SiMaC is a promsing resin for Sr adsorption and recovery.
This paper examines the diversification of overseas subsidiaries on innovation performance of the parent company. Based on theoretical analysis and a combined Chinese firm dataset from 2000 to 2013, ...we find that diversification of overseas subsidiaries positively promotes the parent company innovation performance through the spillover effect of innovation capabilities. In addition, we determine that both the overseas and domestic investment layout can positively moderate the main effect. But there are differences between them. In concrete terms, the domestic investment layout plays a substitution effect in developed areas and acts a more pronounced moderating role in state-owned sample. Besides, the overseas investment layout plays a more important substitutive moderating role on non-state-owned enterprises. This research provides a special insight for studying the reverse spillover effect of OFDI in terms of the contribution of subsidiary linkages and offers several recommendations for multinational corporations to enhance the global competitiveness.
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