Paving the path towards carbon neutrality: revealing the contribution of the "Belt and Road" Initiative in mitigating carbon intensity.

This study explores the crucial contribution of the "Belt and Road" Initiative (BRI) in diminishing carbon intensity and facilitating progress towards carbon neutrality, addressing the pressing global issue of climate change. Given its status as the world's foremost carbon emitter, China encounters significant pressure to alleviate its emissions. Launched in 2013, the BRI emphasizes economic development along its route while highlighting environmental protection in the regions involved. Despite extensive analyses of the BRI's economic impact, its environmental consequences have received insufficient attention, hindering a comprehensive evaluation of the initiative and obstructing the constructing of an environmentally optimal road. Empirical findings reveal a substantial reduction in carbon emission intensity in provinces along the BRI route, with robustness tests (change the time window period and dynamic effect) validating result consistency. The BRI achieves this reduction by alleviating congestion, enhancing transportation infrastructure, fostering commuting agglomeration, optimizing energy utilization, and lowering carbon intensity. Further analysis uncovers a mediating chain effect, establishing a conduction mechanism of "BRI brings on transportation infrastructure effect and then leads to travel agglomeration effect and then to congestion improvement effect and then to energy utilization effect and then eventuates carbon intensity reduction." This study offers crucial insights for policymakers aiming to make informed decisions towards the green road construction of the BRI, contributing to global efforts to combat climate change.

Alkyl modified cationic COFs for preferential trapping of charge dispersed perrhenate: Synergistic hydrophobicity and anion-recognition effects.

Charge dispersed oxoanionic pollutants (such as TcO4- and ReO4-) with low hydrophilicity are typically difficult to be preferentially extracted. Recently, cationic covalent organic frameworks (COFs) have received considerable attention for anions trapping. Two cationic COFs, denoted as Tp-S and Tp-D, were synthesized by incorporating ethyl and cyclic alkylated diquats into 2,2'-bipyridine-based COF. A synergistic effect of hydrophobic channel and anion-recognition sites were achieved by branched chains, which effectively surmounted the Hofmeister bias. Both Tp-S and Tp-D exhibited raising removal performance for surrogate ReO4- at high acidity with adsorption capacities of 435.6 and 291.4 mg g-1, respectively. Obvious variations caused by side chains were displayed in microstructures and adsorption performance. Specially, compared with Tp-D, Tp-S demonstrated desirable priority in uptake capacity and selectivity. In a real-scenario experiment, Tp-S could remove 72.8 % of ReO4- in a simulated Hanford LAW stream, which was attributed to the spatial effects and charge distribution arising from the open and flexible side chains of Tp-S. Otherwise, the rigid cyclic chains endowed pyridine-base Tp-D material an unprecedented alkaline stability. Spectra and theoretical calculations revealed a mechanism of preferential capture based on electrostatic interaction and hydrogen bonding between charge dispersed ReO4-/TcO4- and Tp-S/Tp-D. This work provides an innovative perspective to tailored materials for the treatment of oxoanionic contaminants.

Side-Chain-Assisted Transition of Conjugated Polymers from a Semiconductor to Conductor and Comparison of Their NO2 Sensing Characteristics.

To investigate the effect of a side chain on the electrical properties of a conjugated polymer (CP), we designed two different CPs containing alkyl and ethylene glycol (EG) derivatives as side chains on the same conjugated backbone with an electron donor-acceptor (D-A) type chain configuration. PTQ-T with an alkyl side chain showed typical p-type semiconducting properties, whereas PTQ-TEG with an EG-based side chain exhibited electrically conductive behavior. Both CPs generated radical species owing to their strong D-A type conjugated structure; however, the spin density was much greater in PTQ-TEG. X-ray photoelectron spectroscopy analysis revealed that the O atoms of the EG-based side chains in PTQ-TEG were intercalated with the conjugated backbone and increased the carrier density. Upon application to a field-effect transistor sensor for PTQ-T and resistive sensor for PTQ-TEG, PTQ-TEG exhibited a better NO2 detection capability with faster signal recovery characteristics than PTQ-T. Compared with the relatively rigid alkyl side chains of PTQ-T, the flexible EG-based side chains in PTQ-TEG have a higher potential to enlarge the free volume as well as improve NO2-affinity, which promotes the diffusion of NO2 in and out of the PTQ-TEG film, and ultimately resulting in better NO2 detection capabilities.

Decoupled Control of Grasp and Rotation Constraints During Prehension of Weightless Objects.

Gravity provides critical information for the adjustment of body movement or manipulation of the handheld object. Indeed, the changes in gravity modify the mechanical constraints of prehensile actions, which may be accompanied by the changes in control strategies. The current study examined the effect of the gravitational force of a handheld object on the control strategies for subactions of multidigit prehension. A total of eight subjects performed prehensile tasks while grasping and lifting the handle by about 250 mm along the vertical direction. The experiment consisted of two conditions: lifting gravity-induced (1g) and weightless (0g) handheld objects. The weightless object condition was implemented utilizing a robot arm that produced a constant antigravitational force of the handle. The current analysis was limited to the two-dimensional grasping plane, and the notion of the virtual finger was employed to formulate the cause-effect chain of elemental variables during the prehensile action. The results of correlation analyses confirmed that decoupled organization of two subsets of mechanical variables was observed in both 1g and 0g conditions. While lifting the handle, the two subsets of variables were assumed to contribute to the grasping and rotational equilibrium, respectively. Notably, the normal forces of the thumb and virtual finger had strong positive correlations. In contrast, the normal forces had no significant relationship with the variables as to the moment of force. We conclude that the gravitational force had no detrimental effect on adjustments of the mechanical variables for the rotational action and its decoupling from the grasping equilibrium.

Even-odd chain dependent spin valve effect on a zigzag biphenylene nanoribbon junction.

The even-odd chain dependent spin valve effect was forecasted in some honeycomb graphene-like materials with zigzag edges. In this study, we confirm that the even-odd chain related spin valve phenomenon also exists in a zigzag biphenylene nanoribbon (ZBN) junction. By modeling the ZBN junction with different even and odd chains subjected to a local Rashba spin-orbit coupling (SOC) and a homogeneous magnetic field, we calculate the spin dependent conductance spectra between the source and the drain electrodes and find that the spin up (down) electron can be inhibited (allowed) to flow through the even (odd)-chain ZBN junction, which can be explained by the combined effect between the pseudo-parity conservation and magnetic field-tunable energy gap in the energy band theory. The switch on and off states of spin valve can be modulated by the most system parameters such as the Fermi energy, magnetic flux, and Rashba SOC. Furthermore, the ZBN can act as a gate-tunable spin generator and spin filter, in which we can get 100% polarized spin up (down) electrons with (no) spin-flipping from the even-chain ZBN junction, and only produce 27% polarized spin-converting electrons from the odd-chain ZBN junction. Our findings might be useful in designing future multi-parameter controllable spin valves by using the new carbon allotropes.

Significantly Enhanced Molecular Stacking in Ternary Bulk Heterojunctions Enabled by an Appropriate Side Group on Donor Polymer.

Ternary strategy is a promising approach to broaden the photoresponse of polymer solar cells (PSCs) by adopting combinatory photoactive blends. However, it could lead to a more complicated situation in manipulating the bulk morphology. Achieving an ideal morphology that enhances the charge transport and light absorption simultaneously is an essential avenue to promote the device performance. Herein, two polymers with different lengths of side groups (P1 is based on phenyl side group and P2 is based on biphenyl side group) are adopted in the dual-acceptor ternary systems to evaluate the relationship between conjugated side group and crystalline behavior in the ternary system. The P1 ternary system delivers a greatly improved power conversion efficiency (PCE) of 13.06%, which could be attributed to the intense and broad photoresponse and improved charge transport originating from the improved crystallinity. Inversely, the P2 ternary device only exhibits a poor PCE of 8.97%, where the decreased device performance could mainly be ascribed to the disturbed molecular stacking of the components originating from the overlong conjugated side group. The results demonstrate a conjugated side group could greatly determine the device performance by tuning the crystallinity of components in ternary systems.

Effect of Side Chain Length on Polycarboxylate Superplasticizer in Aqueous Solution: A Computational Study.

Molecular dynamics simulations were carried out to study the conformations of polycarboxylate ether (PCE) superplasticizers with different side chain lengths in aqueous solution. For four types of PCE molecules-PCE1, PCE2, PCE3, and PCE4-the steric hindrance between the PCE molecules increased with increasing side chain length. The side chain length not only affects water mobility but also affects the distribution of water molecules in the system. Simulation results indicate that water molecules were trapped by the PCE molecules, reducing the diffusion properties. PCE molecules with long side chains have more water molecules probability around the main chain and fewer water molecules probability near the side chain. Microscopic-level knowledge of the interaction between superplasticizer and water molecules facilitates understanding of the performance of superplasticizers in cement systems.

FTIR Spectroscopy Suggests a Revised Mode of Action for the Cationic Side-Chain Effect of Ionic Liquids.

Over the past decades, ionic liquids (ILs) have gained considerable attention from the scientific community because of their versatile and designable properties. As a result, there are numerous IL applications, not only in organic synthesis, catalysis, or extraction but also as active pharmaceutical ingredients or novel antimicrobials. While considerable effort has been put into developing quantitative structure-activity relationship (QSAR) models for IL toxicity prediction, little is known about their actual mode of action. In this study, Fourier transform infrared (FTIR) spectroscopy is used to monitor IL induced molecular responses directly at the cellular level. Investigation of the well-known cationic alkyl side-chain effect (increasing side-chain length leads to increasing toxicity) of imidazolium- and ammonium-based ILs on two bacterial pathogens, enteropathogenic  Escherichia coli (EPEC) and methicillin-resistant Staphylococcus aureus (MRSA), surprisingly revealed two distinct modes of action. Contrary to prior models, it was only for [TMC16A][Cl], where a molecular response in the membrane was found, while ILs with shorter side-chain lengths predominantly affected bacterial proteins. The results of this study highlight the importance of further direct investigations of the impact of ILs at the cellular level to improve toxicity prediction and assess the usefulness of spectroscopic methods, such as FTIR spectroscopy at achieving this goal.

Benzodithiophene-Dithienylbenzothiadiazole Copolymers for Efficient Polymer Solar Cells: Side-Chain Effect on Photovoltaic Performance.

A new series of low band gap D-A alternating polymers based on 4,5-bis((2-ethylhexyl)oxy)benzo[2,1- b:3,4- b']dithiophene (BDT) and 5-fluoro-4,7-bis(4-alkylthien-2-yl)benzo[ c][1,2,5]thiadiazole bearing different size of lateral alkyl substituents, namely, PfBB- n, n = 8, 10, 12, 14, and 16, was designed and synthesized for high-performance bulk heterojunction (BHJ) polymer solar cells (PSCs). PfBB- n-bearing linear alkyl side chains exhibited strong and controllable aggregation in both solution and solid states, which gives rise to a significant bathochromic shift of the absorption cut-off down to ∼780 nm in thin film. In addition, the strong and wide absorption (350-800 nm) of PfBB- n polymers can compensate for the relatively weak absorption of PC71BM, particularly in the 300-400 range nm to enhance light harvesting of such an active blend. BHJ solar cells based on PfBB- n:PC71BM blends as an active layer showed power conversion efficiency (PCE) in the range 7.8-9.7%. Because of the strong stacking interchain interactions, PfBB-12-based PSC exhibited aggregation-induced spectral broadening, superior structural order, higher exciton dissociation, higher and more balanced charge carrier mobilities, as well as reduced recombination losses. As a result, PfBB-12-based device afforded the best PCE of 9.7%, with the highest short-circuit current density ( Jsc) of 16.6 mA cm-2 and open-circuit voltage ( Voc) of 0.92 V among devices fabricated. These results demonstrate that the alkyl side chain of the polymer significantly affects the absorption, morphology, and electronic properties of the active blend of PfBB- n/PC71BM, which would provide an alternative useful tool to fine-tune the device performance. Our results also highlight that the electron-rich benzo[2,1- b:3,4- b']dithiophene building block, BDT, is highly useful for the construction of low band gap D-A polymer for highly efficient PSCs.

Effect of alkyl chain on cellular uptake and antitumor activity of hydroxycamptothecin nanoparticles based on amphiphilic linear molecules.

Drug-loaded nanoparticles utilizing amphiphilic molecules as nanocarriers were developed broadly for nanoscale drug delivery system. Linear amphiphilic molecule (PEG45C18) based on PEG and alkyl chain was designed and synthesized. To study the influence of alkyl chain on antitumor activity, 10-hydroxycamptothecin (HCPT) was selected as the hydrophobic drug, amphiphilic molecule (PEG45C18) and hydrophilic PEG (PEG45) were applied as nanocarriers to form HCPT-loaded nanoparticles (HCPT/PEG45C18 NPs and HCPT/PEG45 NPs). These two nanoparticles presented high drug-loading content, stability, but different release manner and antitumor efficacy. The HCPT/PEG45C18 NPs existed slower release manner but higher antitumor activity than HCPT/PEG45 NPs, IC50 value was decreased approximately 8.5-fold against 4T1 cells in vitro. Moreover, the antitumor efficacy of HCPT/PEG45C18 NPs on 4T1-bearing mice was promoted significantly, the inhibition rate based on average tumor weight was 1.5-fold higher than HCPT/PEG45 NPs, besides, HCPT/PEG45C18 NPs exhibited better tumor accumulation than HCPT/PEG45 NPs. These results suggested alkyl chain affect the antitumor activity significantly due to nanoparticles decorated with alkyl chains existing higher endocytosis efficacy to cells. According to the enhanced antitumor efficacy, it was suggested that HCPT/PEG45C18 NPs showed the potential application for cancer therapy in clinic, and alkyl chains should be considered for designing biomaterials.

Evidence of a reverse side-chain effect of tris(pentafluoroethyl)trifluorophosphate [FAP]-based ionic liquids against pathogenic bacteria.

Increased interest in ionic liquids (ILs) is due to their designable and tunable unique physicochemical properties, which are utilized for a wide variety of chemical and biotechnological applications. ILs containing the tris(pentafluoroethyl)trifluorophosphate ([FAP]) anion have been shown to have excellent hydrolytic, electrochemical and thermal stability and have been successfully used in various applications. In the present study the influence of the cation on the toxicity of the [FAP] anion was investigated. Due to the properties of [FAP] ILs, the IL-toxicity of seven cations with [FAP] compared to [Cl] was examined by determination of minimum inhibitory (MIC) and minimum bactericidal concentrations (MBC) on six Gram-positive and six Gram-negative clinically-relevant bacteria. For the first time, to our knowledge, the results provide evidence for a decrease in toxicity with increasing alkyl side-chain length, indicating that the combination of both ions is responsible for this 'reverse side-chain effect'. These findings could portend development of new non-toxic ILs as green alternatives to conventional organic solvents.

Virucidal Influence of Ionic Liquids on Phages P100 and MS2.

An increasing number of publications describe the potential of ionic liquids (ILs) as novel antimicrobials, antibacterial coatings and even as active pharmaceutical ingredients. Nevertheless, a major research area, notably their impact on viruses, has so far been neglected. Consequently the aim of this study was to examine the effects of ILs on the infectivity of viruses. A systematic analysis to investigate the effects of defined structural elements of ILs on virus activity was performed using 55 ILs. All structure activity relationships (SARs) were tested on the human norovirus surrogate phage MS2 and phage P100 representing non-enveloped DNA viruses. Results demonstrate that IL SAR conclusions, established for prokaryotes and eukaryotes, are not readily applicable to the examined phages. A virus-type-dependent IL influence was also apparent. Overall, four ILs, covering different structural elements, were found to reduce phage P100 infectivity by ≥4 log10 units, indicating a virucidal effect, whereas the highest reduction for phage MS2 was about 3 log10 units. Results indicate that future applications of ILs as virucidal agents will require development of novel SARs and the obtained results serve as a good starting point for future studies.

Asymmetric Alkylthienyl Thienoacenes Derived from Anthra[2,3-b]thieno[2,3-d]thiophene for Solution-Processable Organic Semiconductors.

Anthra[2,3-b]thieno[2,3-d]thiophene (ATT), which is readily accessed from thieno[3,2-b]thiophene and 2,3-naphthalenedicarboxylic anhydride, allows for selective substitution at the terminal thiophene ring, thereby providing asymmetric monoalkyl and monoalkylthienyl thienoacenes. Alkyl-substituted ATT (CnATT, n = 6, 8, 10, 12) has characteristics of a p-type field-effect transistor (FET), with mobility on the order of 0.01 cm2 V-1 s-1, which is the same as ATT. Conversely, alkylthienyl-substituted ATT (CnTATT, n = 6, 8, 10, 12) exhibits FET mobility of 0.15-1.9 cm2 V-1 s-1, which is up to 2 orders of magnitude greater than that of ATT and CnATT. Moreover, CnTATT forms crystalline thin films both by spin coating and drop casting, and C8TATT in particular exhibits a mobility of up to 1.6 cm2 V-1 s-1 in the drop-cast film. X-ray diffraction patterns of CnTATT thin films indicate that the molecules become oriented edge-on at the substrate surface with a highly ordered structure in the in-plane direction. Accordingly, CnTATT serves as a solution-processable p-type organic field-effect transistor, where the additional thiophene ring contributes significantly to the highly ordered thin-film structure and the high carrier mobility.

Epindolidione-Based Conjugated Polymers: Synthesis, Electronic Structures, and Charge Transport Properties.

Development of new electron-deficient building blocks is essential to donor-acceptor conjugated polymers. Herein, epindolidione (EPD) as electron-deficient unit was integrated into conjugated polymers for the investigation of field-effect transistors for the first time. We systematically studied the electronic structures and charge transport properties of the EPD-based donor-acceptor polymers. They exhibit p-type transport characteristics with the highest mobility of up to 0.40 cm(2) V(-1) s(-1), thus demonstrating its great potential as a building block for polymer field-effect transistors and photovoltaics.

A BDOPV-based donor-acceptor polymer for high-performance n-type and oxygen-doped ambipolar field-effect transistors.

An electron-deficient building block BDOPV is developed to construct a new donor-acceptor conjugated polymer BDOPV-2T for high-performance n-type and oxygen-doped ambipolar polymer field-effect transistors. A high electron mobility up to 1.74 cm(2) V(-1) s(-1) is demonstrated under ambient conditions. Furthermore, the oxygen-doping effect and possible mechanism are discussed.

Contaminated food and uptake of heavy metals by fish: a review and a proposal for further research.

1. The uptake of heavy metals via the alimentary tract can be an important factor for the metal budget of fish. 2. Concepts such as biomagnification, bioaccumulation, biotransference, or concentration factors, convey little information about the real threat originating from heavy metals in an aquatic food chain. 3. In polluted aquatic ecosystems the transfer of metals through food chains can be high enough to bring about harmful concentrations in the tissues of fish. This relationship is called the food chain effect. 4. Two kinds of ecological factors influence the food chain effect: firstly, high levels of contamination of the food, and, secondly, the reduction of species diversity. When susceptible species are eliminated, metal-tolerant food organisms may become dominant. Their tolerance may be based either on their ability to accumulate excessive amounts of metals or to exclude heavy metals from the tissues. These two strategies represent feedback mechanisms which may enhance or weaken the food chain effect. 5. It is concluded that future investigations on transference of heavy metals to fish must take into more careful consideration the specific ecological situation of a given environment.