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Treatment of azo compounds with an η2-alkyne-coordinated metallacycle via alkyne-azo coupling followed by aromatization efficiently afforded the first diaza-metallapentalenes.

Aromatic metallacycles are of considerable current interest. Reported aromatic metallacycles are mainly those with carbon, nitrogen, oxygen and sulfur. In this work, we report the synthesis and characterization of aromatic chloroosmacyclopentatrienes, which represent the first structurally confirmed metallaaromatic with a chlorine atom in its framework. Single-crystal X-ray diffraction studies show that these planar chloroosmacyclopentatrienes possess a very short Os–ClC distance suggesting M=ClC bond character.

Metalla-aromatics are important complexes that show unique properties owing to their highly conjugated systems, which show Huckel or Mobius aromaticity. Recently, several metalla-aromatics showing spiro-aromaticity or σ-aromaticity have been reported. Herein, we report the isolation of the first cyclopropametallanaphthalenes, in which the metallacyclopropene ring shows σ-aromaticity and weak hyperconjugative aromaticity. The reaction of OsCl2 (PPh3 )3 with o-ethynylphenyl alkynes in the presence of PPh3 followed by protonation with HCl yielded the first cyclopropametallanaphthalenes. The reaction mechanism and the aromaticity were also investigated by density functional theory studies.

China&rsquo, s construction industry is facing significant challenges in achieving sustainable development and digital operations. Integrating building information modeling (BIM) and sustainable construction is a good method for achieving these goals. However, barriers impact the applications of BIM technology to sustainable buildings, resulting in significant cost loss and time. As such, it is important to identify the constraints, hindering the application of BIM technology in sustainable buildings. This study used the factor analysis method, exploratory factor analysis (EFA), and structural equation modeling (SEM) to investigate the key constraints and conducted a questionnaire survey with 389 respondents to investigate the applications of BIM technology in sustainable building projects. The results showed that there were four main constraining factors: &ldquo, Public participation&rdquo, &ldquo, technology application&rdquo, economic cost&rdquo, and &ldquo, application management&rdquo, public participation&rdquo, was particularly important. The study offers practical and managerial implications based on the findings for local government and the private sector and thus can improve the implementation of BIM technology in sustainable buildings and contribute to the accomplishment of China&rsquo, s sustainable development goals.

This paper mainly focuses on the synergistic effect of Sn and N dopants to enhance the photocatalytic performance of anatase TiO2 under visible light or simulated solar light irradiation. The Sn and N co-doped TiO2 (SNT-x) photocatalysts were successfully prepared by the facile sol-gel method and the post-nitridation route in the temperature range of 400-550 °C. All the as-prepared samples were characterized in detail by X-ray diffraction, UV-vis diffuse reflectance spectroscopy, transmission electron microscopy, X-ray photoelectron and electron spin resonance spectroscopy and photoelectrochemical measurements. The characterization results reveal that the co-incorporation of Sn and N atoms remarkably modifies the electronic structure of TiO2, which gives rise to a prominent separation of photogenerated charge carriers and more efficient interfacial charge-transfer reactions in a photocatalytic process. The enhanced photocatalytic activity is attributed to the intensified active oxygen species including hydroxyl radicals (˙OH) and superoxide anion radicals (O2˙(-)) for degradation of organic pollutants. And the result of photocatalytic hydrogen production further confirms the existence of the synergistic effect in the SNT-x samples, because they exhibit higher photocatalytic activity than the sum of N/TiO2 and Sn/TiO2. This work provides a paradigm to consolidate the understanding of the synergistic effect of metal and non-metal co-doped TiO2 in domains of photocatalysis and photoelectrochemistry.

Treatment of the SiMe3 -protected dichloro-rhenium carbyne complexes Re{≡CCH=C(R)C≡CSiMe3 }Cl2 (PMe2 Ph)3 (R = CMe3 , 1-adamantyl) with CsF in methanol directly afforded the 12-membered metallacycles {ReCl(PMe2 Ph)3 }2 {≡CCH=C(R)C≡C-}2 . The electronic structure of the metallacycle was investigated by density functional calculations. The UV-vis spectrum of the metallacycle shows a red-shifted band compared to that of the starting dichlorocarbyne complex. Treatment of {ReCl(PMe2 Ph)3 }2 {≡CCH=C(CMe3 )C≡C-}2 with HCl produced the dichloro-rhenium carbyne complex Re{≡CCH=C(CMe3 )C≡CH}Cl2 (PMe2 Ph)3 , which is consistent with the electronic structure of the 12-membered metallacycles.

Building information modeling (BIM) is based on 3D models for collaborative management of information, which leads the innovative development of information transformation in the construction industry. In recent years, sustainable construction has become a hot topic in construction research. With the concept of sustainable development, this type of construction advocates for the sustainable optimization of construction models and processes. A person&rsquo, s good behavior can bring enormous potential, which is critical for the promotion of new technology in new areas. Nowadays, the integration of BIM technology and sustainable construction has increasingly attracted attention in the industry of construction. But many issues and gaps still exist when using them. The aim of this study is to investigate the intrinsic relationship between BIM application and sustainable construction from the perspective of user application behavior, and to reveal the key influential factors of BIM application behavior in order to improve the application efficiency of BIM in sustainable construction. Specifically, the present study builds a theoretical model by integrating the theory of planned behavior and BIM application. Based on a questionnaire survey of 353 BIM users, we conducted an empirical analysis using the structural equation model method. The results showed that the perceived usefulness and ease of use of BIM technology are the key influential factors in behavior attitude. BIM behavior intention, actual behavior, and behavior attitude have a positive effect on sustainable construction. Ultimately, practical support is provided for the effective integration of BIM with sustainable construction in China.