查找使用阿拉丁产品的科研文献

Urchin-like Ni@N-doped carbon composites with Ni nanoparticles encapsulated in N-doped carbon nantubes as high-efficient electrocatalyst for oxygen evolution reaction

Hongjie Li,Yi He,Qiangbing Yang,Jizhuang Wang,Siming Yan,Chunlin Chen,Jingyu Chen

Electrospinning and carbonization have been combined to fabricate urchin-like nickel nanoparticle@ nitrogen doped carbon composites electrocatalysts for efficient oxygen evolution reaction (OER), in which bamboo-like and graphic N-doped carbon nanotubes encapsulated nickel nanoparticles can be detected on the substrates’ surface. The catalyst has superior performance in OER shows a low overpotentials of 305 mV at 10 mA cm −2 , small Tafel slope of 62 mV·dec −1 and outstanding durability. In addition, the research opens a simple route to develop high-efficient OER electrocatalyst from earth-abundant materials.

Mechanical Properties and Thermal Degradation Kinetics of a Novel Thermally Stable Thermoplastic Poly(ester-ether) Elastomer Containing N′N-Bis(2-carboxymethyl) Pyromellitimide Unit

Shaojian Lin,Jiaojiao Shang,Jianwu Lan,Ronghui Guo,Xia Huang,Wen He

Preparation, Mechanical Properties and Thermal Degradation Kinetics of a Novel Poly(ester-ether-imide) Elastomer Based on N′,N-Bis(2-hydroxyethyl)-Pyromellitimide Unit

Shaojian Lin,Jianwu Lan,Ronghui Guo,Jiaojiao Shang,Wen He

Rapid and Cost-Effective Synthesis of Nanosized Zeolitic Imidazolate Framework-7 with N,N′-Dimethylformamide as Solvent and Metal Acetate Salt as Metal Source

Xiang Wang,Pengcheng Huang,Ping Yu,Lifen Yang,Lanqun Mao

In this study, a new method was developed for the rapid and cost-effective synthesis of nanosized zeolitic imidazolate framework-7 (ZIF-7) nanocrystals with a high yield and a low molar ratio of benzimidazole ligand to metal salt (2:1) by using N , N′- dimethylformamide (DMF) as the solvent and zinc acetate dihydrate (Zn(OAc) 2 ⋅2 H 2 O) as the metal source. The synthesized ZIF-7 nanocrystals have a size of approximately 50–80 nm, and tend to aggregate or become intergrown to form irregular nanoparticles of about 200–300 nm in size. The morphology and yield of the ZIF-7 nanocrystals can be tuned easily by changing the synthetic parameters such as the composition of the solvent and concentrations of reagents. The synthesized ZIF-7 nanocrystals exhibit good thermal and chemical stability, CO 2 capture capability, and fluorescent properties. Remarkably, we find that the synthetic strategy developed here can be extended to the syntheses of other kinds of ZIFs including ZIF-69 and ZIF-90. This study offers a new, simple synthetic strategy for the high-yield preparation of ZIF materials. Graphical Zeolitic nanocrystal control : We have developed a new method for the rapid and cost-effective synthesis of nanosized zeolitic imidazolate framework (ZIF-7) nanocrystals with a high yield and a stoichiometric molar ratio of ligand to metal salt (2:1) by using N , N ′-dimethylformamide (DMF) as the solvent and zinc acetate as the metal source (see figure). This strategy can also be extended to the synthesis of ZIF-69 and ZIF-90.

Ban+2Znn(BO3)n(B2O5)Fn (n = 1, 2): new members of the zincoborate fluoride series with two kinds of isolated B–O units

Miriding Mutailipu,Xin Su,Min Zhang,Zhihua Yang,Shilie Pan

Two new members of zincoborate fluoride series Ban+2Znn(BO3)n(B2O5)Fn (n = 1, 2), namely, Ba3Zn(BO3)(B2O5)F and Ba4Zn2(BO3)2(B2O5)F2 were firstly synthesized as high-quality single crystals via a high-temperature solution method by adjusting the molar ratios of reactants. They were structurally determined by single-crystal X-ray diffraction and their structures can be regarded as three dimensional (3D) framework stacking of 2∞[Zn2B6O16]10− layers for Ba3Zn(BO3)(B2O5)F and 2∞[Zn2B4O8O5/2O1/3]17/3− layers for Ba4Zn2(BO3)2(B2O5)F2. To the best of our knowledge, the two title compounds are the first examples of two kinds of isolated B–O groups that coexist in one zincoborate halide. The structure comparisons were carried out among all the available anhydrous-zincoborates, and it is interesting to conclude that about 80% of zincoborates contain isolated B–O clusters and notably the molar ratio of cation/boron (A/B) affects the polymerization of isolated B–O configuration. What's more, the first-principles calculations, infrared spectra, and UV-vis-NIR diffuse reflectance spectra of title compounds have also been performed.

An Overlooked Source of Nitrosamines from Tire-Derived Amine Additives: The Contribution and Transformation Mechanism of N-Isopropyl-N′-phenyl-p-phenylenediamine (IPPD) during Chlorination

Chenglin Liu,Zhong Zhang,Siyuan Xiong,Sheng Wan,Zeyu Chen,Yao Cheng,Bintian Zhang,Xin Yang,Guomao Zheng

Identification of disinfection byproducts (DBPs) precursors remains a longstanding challenge due to the complexity of contaminated source water. Tire wear particles (TWPs) can be an overlooked source of DBPs precursors. To figure out the specific amine additives in tire rubber serving as potential nitrosamine precursors during chlorination, six frequently measured tire-derived amine additives, including N-(1,3-dimethylbutyl)-N′-phenyl-p-phenylenediamine (6PPD), N-isopropyl-N′-phenyl-p-phenylenediamine (IPPD), N-cyclohexyl-N′-phenyl-p-phenylenediamine (CPPD), N,N′-dicyclohexylurea (DCU), diphenylamine (DPhA), and N,N′-dicyclohexylamine (DCHA), were selected to simulate their degradation processes, and their DBPs formation potentials were evaluated under various water matrices. IPPD was found to have a high molar yield of N-nitrosodimethylamine (NDMA, up to 8%), while 6PPD exhibited a lower molar yield (∼0.1%) with the molar ratio of chlorine-to-ammonium nitrogen (Cl2:N = 2) and disinfectant-to-precursor (D/P = 10). Suspect and target screening approaches were further applied to identify the transformation products of IPPD, and the formation pathway of NDMA via IPPD was proposed. Furthermore, we assessed NDMA formation from IPPD in simulated TWP leachates through chlorination experiments in the presence of ammonia, which revealed that IPPD contributed up to 24% of the total NDMA formed. This study offers new insights into the previously overlooked source of nitrosamines from tire-derived amine additives.

Experimental and modeling study of the autoignition for diesel and n-alcohol blends from ethanol to n-pentanol in shock tube and rapid compression machine

Sixu Wang,Yueying Liang,Jizhen Zhu,Mohsin Raza,Jing Li,Liang Yu,Yong Qian,Xingcai Lu

The ignition delay times (IDTs) of n-alcohol/diesel blends were measured in a heated shock tube (ST) and a heated rapid compression machine (RCM). Three sets of blends were formulated to investigate the effect of n-alcohol (the volume ratio of n-alcohol/diesel being 20%/80% for four blends), cetane number (CN = 43, the volume ratio of n-alcohol/diesel being 20%/80% ethanol/diesel, 20.5%/79.5% n-propanol/diesel, 23.5%/76.6% n-butanol/diesel, 25.8%/74.2% n-pentanol/diesel), and oxygen content (mass fraction of oxygen w O2  = 6.65%, the volume ratio of n-alcohol/diesel being 20%/80% ethanol/diesel, 25.6%/74.4% n-propanol/diesel, 31.4%/68.6% n-butanol/diesel, 37.2%/62.8% n-pentanol/diesel) on the autoignition characteristics. In the RCM temperature region, the IDTs decrease with increasing n-alcohol chain length from ethanol to n-pentanol for all three sets of blends, while those in the ST temperature region show indiscernible variations. Interestingly, the intersection of IDTs for ethanol/diesel blend with other n-alcohol/diesel blends is observed when the temperature is below ~700 K. A recently-released detailed mechanism from the CRECK modeling group was used to predict the experimental results. The simulations show relatively good agreement with high-temperature (HT) ignition data, while the mechanism pronouncedly overpredicts the reactivity of blends at low-to-intermediate temperatures. Sensitivity analyses at three temperatures of 675 K, 800 K, and 1300 K were conducted to identify the dominant reactions during the autoignition of 20% n-alcohol/80% diesel blends and to kinetically elaborate and discuss the discrepancies between simulations and experiments. At the end, a preliminary mechanism tune-up was carried out grounded on the sensitivity analyses. The improved mechanism regains its predictive ability for IDTs of 20% n-butanol/80% diesel blend at RCM temperatures, while fails to precisely simulate the remaining three blends.

Synergistic effect of p-type semiconductor n-Co3O4@C-N on the flame retardancy, smoke suppression, and toxicity reduction of linear low-density polyethylene composites

Jiaqi Geng,Zhichao Tian,Ruiping Wang,Junxiu Liu,Miaojun Xu,Huiying Wen,Mingyang Zhu,Bin Li

Linear low-density polyethylene (LLDPE) is flammable and produces severe molten droplets and toxic smoke, posing a great threat to life and property safety. To address these challenges, ZIF−67-derived nano-carbon-nitrogen-coated Co 3 O 4 (n-Co 3 O 4 @C-N) was synthesized and employed as a synergist for an intumescent flame retardant (IFR) in LLDPE. When IFR/n-Co 3 O 4 @C-N was introduced, LLDPE composites achieved a UL−94 V−0 rating and the limiting oxygen index of 26.8%. Cone calorimeter test results further demonstrated that the total heat release of LLDPE/IFR/n-Co 3 O 4 @C-N−3 decreased by 23.2% compared with pure LLDPE, indicating remarkable suppression of fire intensity. Compared with LLDPE/IFR and LLDPE/commercial-Co 3 O 4 , LLDPE/IFR/n-Co 3 O 4 @C-N−3 exhibited a reduction in total smoke production by 50.3% and 37.2%. The high specific surface area of n-Co 3 O 4 @C-N facilitates sufficient contact with the polymer matrix, enhancing catalytic carbonization and forming a robust graphitized char layer. Furthermore, as a p-type semiconductor, n-Co 3 O 4 @C-N has a narrower band gap, reducing the energy required for electron transition, and its higher hole concentration helps to oxidize more CO to low-toxicity CO 2 , thereby lowering the concentration of toxic gases. This study presents a promising strategy to fabricate flame-retardant, smoke-suppressing, and low-toxic LLDPE composites, thus effectively overcoming the existing technical limitations in wire and cable application fields.

Synergistic regulation of surface O/N active sites and local conjugation in N-doped carbonized polymer dots for smartphone-assisted dual-mode sensing of Hg2+

Tao Li,Weitao Wang,Boyang Dou,Shudie Shen,Wenli Zhao,Yanfei Wang,Xiaoyu Zhao,Botao Teng,Liang Zhu

The development of portable, sensitive, and interference-resistant platforms for on-site Hg 2+ detection in aquatic food samples remains highly desirable for food safety monitoring. Herein, a smartphone-assisted fluorescence/colorimetric dual-mode sensing platform was constructed based on N-doped carbonized polymer dots (N-CPDs). The N-CPDs were prepared from ethylenediaminetetraacetic acid and m -phenylenediamine via one-step crosslinking polymerization. By regulating surface O/N active sites and local conjugated structures, the N-CPDs exhibited fluorescence quenching and colorimetric responses toward Hg 2+ without additional responsive reagents. The limits of detection were 40.91 and 38.97 nM for the fluorescence and colorimetric modes, respectively. Structural characterization and quantum chemical calculations indicated that the matching between key oxygen-containing recognition sites and local conjugated structures is critical to the sensing performance. Mechanistic analysis further revealed Hg 2+ -induced static fluorescence quenching and a coordination-driven colorimetric response. Coupled with smartphone-based RGB analysis, the platform enabled portable quantitative detection of Hg 2+ in aquatic food samples, including fish, shrimp, crab, and seaweed. The recoveries were 90.11–108.88%, with RSDs below 4.98%, and the results agreed well with ICP-OES measurements. This work provides an effective strategy for constructing high-performance CPD-based dual-mode sensing platforms and offers a promising tool for portable and reliable Hg 2+ monitoring in real food samples.

Synergistically Coupled CoFe Core–Shell Nanoparticles and Fe–N x Motifs in N,S,P-Doped Hierarchical Carbon for Rechargeable Zinc–Air Batteries

Balamurali Ravichandran,Soujanya Prakash Bammanalli,Muthu Austeria P,Sabarinathan Ravichandran,Huiyuan Liu,Weiqi Zhang,Narayanamoorthy Bhuvanendran,Huaneng Su

Abstract Rechargeable zinc–air batteries (ZABs) require efficient and durable bifunctional oxygen electrocatalysts to accelerate both the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). Herein, we report a hierarchical N, S, and P co-doped carbon catalyst (CoFe/NSP-HC) featuring CoFe core–shell alloy nanoparticles and Fe–Nx coordination motifs, synthesized through a pyrolysis strategy using heteroatom-enriched g-C3N4 as both template and dopant source. Structural characterization reveals a hierarchical porous architecture with uniformly distributed heteroatoms, strong metal–support interactions, and a well-defined Co-rich core/Fe-rich shell configuration. The synergistic integration of CoFe alloy interfaces, Fe–Nx coordination sites, and a defect-rich carbon framework effectively modulates the electronic structure and optimizes the adsorption/desorption behavior of oxygenated intermediates. Consequently, the optimized CoFe/NSP-HC catalyst exhibits bifunctional activity with an ORR half-wave potential of 0.82 V and an OER overpotential of 260 mV at 10 mA cm–2, delivering a low bifunctional potential gap (ΔE) of 0.67 V. Furthermore, the catalyst demonstrates robust electrochemical durability, maintaining stable ORR/OER performance after prolonged cycling. Density functional theory calculations reveal that Fe–Nx sites and Fe-based interfacial centers provide favorable reaction energetics for oxygen electrocatalysis, while Co species contribute to electronic modulation and kinetic enhancement. When employed as the air cathode in a rechargeable ZAB, CoFe/NSP-HC delivers a peak power density of 158.7 mW cm–2 and long-term cycling stability exceeding 350 h. This work provides an effective strategy for constructing multi-component electrocatalysts with synergistically engineered active sites for advanced metal–air energy storage systems.

Solubility of melatonin in ethyl acetate + (N, N-dimethylformamide, 2-methoxyethanol, 2-ethoxyethanol and methanol): Determination, correlation, thermodynamic properties and Hansen solubility parameter at saturation

Renren Sun,Haixia He,Yameng Wan,Yueru Wang,Liyuan Li,Jiao Sha,Gaoliang Jiang,Yu Li,Tao Li,Baozeng Ren

For further study on solubility behaviors of melatonin (MT), the solubility of MT in the three mono-solvents {N, N-dimethylformamide (DMF), 2-methoxyethanol, 2-ethoxyethanol} and four binary solvents {(DMF, 2-methoxyethanol, 2-ethoxyethanol and methanol) + ethyl acetate} was measured in a range of 278.15 K–323.15 K by laser monitoring method. The measurement results showed that MT solubility in all tested solvents increased with rising temperature. In binary solvents except methanol + ethyl acetate, the solubility values of MT had a positive relationship with the mass fraction of co-solvents. In methanol + ethyl acetate, the solubility of MT initially increased, followed by a decrease (with the rising mass fraction of methanol) and arrived the highest solubility value at a mass fraction of methanol being 0.4000. The Hansen solubility parameters (HSPs) were applied to study the solubility behaviors of MT in tested solvents. Moreover, in three pure solvents, the measured solubility data of MT was correlated by (NRTL-SAC, NRTL, two-Suffix Margules, UNIQUAC models and modified Apelblat equation). In binary solvents, the solubility data was fitted by (three-Suffix Margules, λh equation, Yaws model equation and modified Apelblat equation). Furthermore, the apparent thermodynamic properties were calculated based on the van’t Hoff equation. The positive values of apparent standard dissolution enthalpy and entropy suggest that the dissolution process of MT in all of chosen solvents is entropy-driven and endothermic. The larger values of ζ H than ζ TS represent that the main contributor of Δ dis G o in all investigated solvents is enthalpy.

Densities and Viscosities for the Ternary System of Isopropylcyclohexane (1) + n-Tridecane (2) + n-Butanol (3) and Corresponding Binaries at T = 293.15 to 333.15 K

Quan Lei,Yitong Dai,Panxi Wu,Wenjun Fang,Yongsheng Guo

It has been proven that alcohols can regulate the performance of aviation fuels. In this work, the densities (ρ) and viscosities (η) for the ternary system of isopropylcyclohexane (1) + n-tridecane (2) + n-butanol (3) and the corresponding binary systems have been measured to understand the physical properties of endothermic hydrocarbon fuel with alcohol over the whole composition range at temperatures from 293.15 to 333.15 K under atmospheric pressure (p = 0.1 MPa). The Redlich–Kister equation has been used to fit the excess molar volumes (VmE) and viscosity deviations (Δη) of binary systems, while four semiempirical equations (Singh, Cibulka, Nagata–Tamura, and Redlich–Kister) have been applied to correlate VmE and Δη of the ternary system. For all binary systems, the values of VmE are positive. The values of Δη for binary systems containing n-butanol are all negative. For the ternary system, the values of VmE are all positive and the values of Δη are all negative over the entire concentration range. All results have been interpreted with the perspective of intermolecular interaction and structural effect.