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At present, in the project cost management of our country, we are faced with the defects such as large quantity of statistical analysis of fake data, obvious delay of cost data, difficulty in sharing cost data efficiently, etc., the existence of BIM technology is bringing a new technical innovation to the construction field, the introduction of BIM technology in project cost management is undoubtedly the general trend.

Metal-organic frameworks (MOFs) have attracted extensive attention in catalysis and adsorption fields due to the large surface area and tunable pore structure, however MOFs have not been so broadly exploited for water treatment primarily due to their low water stability and hydrophilicity. In this study, a kind of MOFs, poly(acrylic acid) (PAA) modified UiO-66-NH2 (UiO-66-NH2@PAA), was first synthesized and used to fabricate membranes via vacuum-assisted self-assembly process. Owing to the high water adsorption ability of MOF, abundant hydrophilic, negatively-charged carboxyl groups and high surface roughness, the membranes exhibited high hydrophilicity and underwater superoleophobicity, and thus better antifouling performance. Owing to the ionization and deionization ability of carboxyl groups, the membranes exhibited good stability in the pH range from 1 to 11. Owing to the existence of chemical and hydrogen bond interactions, the membranes exhibited improved multicycle stability. Accordingly, the MOF membranes exhibited high separation efficiency for oil/water emulsion (rejection > 99.9%). Under optimum conditions, the pure water flux was 2330 L m−2 h−1 bar−1 and the flux recovery ratio (FRR) after 3 cycles separation of oil/water emulsion maintained over 80%, manifesting great potential of MOF membranes in oil/water separation.

A facile approach to fabricating the antifouling, high-flux oil/water separation carbon nanotube (CNT) nanohybrid membranes was explored by polymer-mediated surface charging and hydrophilization through vacuum-assisted self-assembly process. The controlled stacking of CNT imparted the membranes hierarchical nanostructure and high water permeation reaching 4592 L m −2 h −1 bar −1 , which was about 10 folds of commercial ultrafiltration membranes used for oil/water separation. Modifying CNT with a series of polymers endowed the membranes with different surface charge and hydrophilicity. The compact hydration layer was formed at the interface of water/membrane by the water trapped in the hierarchical nanostructure to prevent oil from adhering on the membrane surface. Hence, the polymer@CNT nanohybrid membranes possessed underwater superoleophobicity and low oil adhesive force. Moreover, the antifouling properties of as-prepared membranes were evaluated through filtration of oil-in-water emulsions with different surface charges and the results demonstrated that synergetically regulating the surface charge and hydrophilicity could tune the interactions between the foulants and membrane surface, which can efficiently inhibit the irreversible fouling, leading to 100% flux recovery ratio (FRR). The fabrication process of the polymer@CNT nanohybrid membranes with high water permeation, high separation efficiency and excellent antifouling properties may enlighten the great prospects for CNT-based materials in water separation and purification.

In order to identify the causal factors of 88 coal and gas outburst accidents and their relationships, this paper proposed a cause classification framework based on the accident causation “2-4” model (24Model). The correlations between the high level and low level causes were analyzed by the Chi-square test for independence. Results showed that root causes, indirect causes and unsafe acts were prevalent in all cases. The main direct causes were violation operation and violation action; the main indirect causes were lack of safety knowledge and low safety awareness; the main radical cause was safety management procedures; the main root causes was safety depending on safety awareness. And there were ten groups of causes with significant correlation between the high level and low level causes. The work paths of different causes in coal and gas outburst accidents were identified by using the proposed cause classification framework.

Membrane separation processes are often perplexed by severe and ubiquitous membrane fouling. Zwitterionic materials, keeping electric neutrality with equivalent positive and negative charged groups, are well known for their superior antifouling properties and have been broadly utilized to construct antifouling surfaces for medical devices, biosensors and marine coatings applications. In recent years, zwitterionic materials have been more and more frequently utilized for constructing antifouling membrane surfaces. In this review, the antifouling mechanisms of zwitterionic materials as well as their biomimetic prototypes in cell membranes will be discussed, followed by the survey of common approaches to incorporate zwitterionic materials onto membrane surfaces including surface grafting, surface segregation, biomimetic adhesion, surface coating and so on. The potential applications of these antifouling membranes are also embedded. Finally, we will present a brief perspective on the future development of zwitterionic materials modified antifouling membranes. Statement of Significance Membrane fouling is a severe problem hampering the application of membrane separation technology. The properties of membrane surfaces play a critical role in membrane fouling and antifouling behavior/performance. Antifouling membrane surface construction has evolved as a hot research issue for the development of membrane processes. Zwitterionic modification of membrane surfaces has been recognized as an effective strategy to resist membrane fouling. This review summarizes the antifouling mechanisms of zwitterionic materials inspired by cell membranes as well as the popular approaches to incorporate them onto membrane surfaces. It can help form a comprehensive knowledge about the principles and methods of modifying membrane surfaces with zwitterionic materials. Finally, we propose the possible future research directions of zwitterionic materials modified antifouling membranes.

Construction of zero-flux-decline membrane surfaces with superior antifouling properties is in great demand for the treatment of oil-water mixture. Inspired by nature, simultaneously incorporating hydrophilic and low-surface-energy groups to form a chemically heterogeneous hydrogel surface holds great promise. In this study, membranes with heterogeneous hydrogel surfaces were fabricated through a one-step reaction enhanced surface segregation method. In details, we synthesized a fluorine-containing copolymer as the modifier in casting solution, and designed tannic acid (TA) aqueous solution as the coagulation bath. During non-solvent induced phase separation, TA can in situ crosslink the modifier at the water-polymer interface through hydrogen bonds, forming a heterogeneous hydrogel layer over the membrane surface. Meanwhile, the hydrophilicity of TA rendered the hydrogel underwater superoleophobic properties. The thickness and chemical composition of the hydrogel layer were facilely manipulated by varying the TA concentration. To our surprise, the unique physicochemical characteristics of heterogeneous hydrogel layer greatly fortified the antifouling mechanisms on membrane surfaces, rendering the membrane zero-flux-decline feature with a flux of 330 L m−2 h−1 at 0.05 MPa during a 60-h cross-flow filtration of five different oil-in-water emulsions.