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The vascular system maintains cellular homeostasis by transporting oxygen, nutrients, and metabolic waste products. The vascular system is involved in a variety of fundamental physiological phenomena and is closely associated with human vascular diseases. Additionally, the stability of drugs in the vasculature affects their efficacy. Therefore, researchers have used vascular models to study vascular diseases, assess drug stability, and screen drugs. However, there are many shortcomings in the animal models and in vitro two-dimensional vascular models that have been extensively developed. In this paper, we specifically review the construction methods of in vitro vascular models and classify the specific methods into photolithography, soft lithography, self-assembly, template, 3D bioprinting, and laser degradation/cavitation. The first two are microfluidics-based methods and the last three are non-microfluidics-based methods. The vascular model construction methods reviewed in this paper overcome the shortcomings of traditional models—which cannot accurately reproduce the human vascular microenvironment—and can assist in the construction of in vitro 3D vascular models and tissue engineering vascularization. These models can be reused by perfusion devices, and the cells within the channels reside on biocompatible materials that are used to simulate the microenvironment and 3D cellular organization of the vasculature in vivo. In addition, these models are reproducible in shape and length, allowing experiments to be repeated, which is difficult to do with natural vessels. In vitro vascular models are widely used in research and drug screening for diseases associated with endothelial dysfunction, cancer, and other vascular abnormalities. [ABSTRACT FROM AUTHOR]

The vascular system maintains cellular homeostasis by transporting oxygen, nutrients, and metabolic waste products. The vascular system is involved in a variety of fundamental physiological phenomena and is closely associated with human vascular diseases. Additionally, the stability of drugs in the vasculature affects their efficacy. Therefore, researchers have used vascular models to study vascular diseases, assess drug stability, and screen drugs. However, there are many shortcomings in the animal models and in vitro two-dimensional vascular models that have been extensively developed. In this paper, we specifically review the construction methods of in vitro vascular models and classify the specific methods into photolithography, soft lithography, self-assembly, template, 3D bioprinting, and laser degradation/cavitation. The first two are microfluidics-based methods and the last three are non-microfluidics-based methods. The vascular model construction methods reviewed in this paper overcome the shortcomings of traditional models—which cannot accurately reproduce the human vascular microenvironment—and can assist in the construction of in vitro 3D vascular models and tissue engineering vascularization. These models can be reused by perfusion devices, and the cells within the channels reside on biocompatible materials that are used to simulate the microenvironment and 3D cellular organization of the vasculature in vivo. In addition, these models are reproducible in shape and length, allowing experiments to be repeated, which is difficult to do with natural vessels. In vitro vascular models are widely used in research and drug screening for diseases associated with endothelial dysfunction, cancer, and other vascular abnormalities.

• RCT Pd/Al 2 O 3 demonstrates high stability under simulated diesel exhaust condition. • RCT Pd/Al 2 O 3 is highly active at low temperature in CO oxidation. • RCT Pd/Al 2 O 3 demonstrates reduced reaction onset temperatures for propane oxidation. • RCT Pd/Al 2 O 3 exhibits exceptional durability after aging at 800 °C for 50 h. • RCT Pd/Al 2 O 3 shows high activity with reduced PGM loading in propane oxidation. It is becoming increasingly urgent to develop and utilize novel, more efficient and stable materials for mobile and stationary emission control applications as the deleterious consequences of anthropogenic air pollution are becoming more evident and pressing. Tightening regulations, particularly related to automotive exhaust treatment, together with continued improvements in engine design, that result in lowering the engine operating temperatures and inadvertently lead to the release of an overwhelming proportion of pollutants during the cold start, present new challenges for materials design, specifically for oxidation catalysts. In particular, improvements in the low-temperature activity while maintaining catalyst stability at high temperatures are required from the next-generation catalyst. Typical catalysts for removal of pollutants from automotive exhaust streams incorporate platinum group metals (PGMs). They tend to be inefficient at low temperatures (below 250 °C), thus accounting for the cold start problem, yet sinter and lose their activity at high temperatures that are frequently encountered during catalyst operation. High PGM loadings are often employed to compensate for catalyst inefficiencies and fast degradation, ultimately resulting in high-cost catalytic converters. We have developed a new approach for the design and formation of catalytic materials that allows for both significantly more efficient PGM incorporation and improved overall catalyst performance at reduced PGM loadings. The method provides control over the composition and geometry of the support through self-assembly of sacrificial composite template — "raspberry" polymeric colloids decorated with catalytic particles — accompanied by infiltration with metal-oxide precursor and subsequent removal of the colloids. This method simultaneously structures the porous network and organizes the catalytic particles within it. Uniquely, the resulting catalytic particles are partially embedded in the support matrix and partially exposed to the pore interior, producing catalytic sites that are both stable and accessible. Herein, the feasibility of this novel and versatile approach for automotive catalytic conversion is demonstrated: the studies include testing alumina-based raspberry-colloid-templated (RCT) catalysts containing Pd nanoparticles (RCT Pd/Al 2 O 3) for oxidation of propane and carbon monoxide under simulated diesel exhaust conditions and hydrothermal aging at 800 °C for 50 h in the simulated stream. The RCT Pd/Al 2 O 3 catalysts exhibit exceptional activity toward CO oxidation, reduced reaction onset temperature, and high stability to elevated temperatures (demonstrated through prolonged exposure to temperatures up to 950 °C) and reactive gas streams, without migration, sintering or loss of the precious metal NPs. Notably, the novel catalyst shows the same or slightly better performance than the commercial catalysts even when the PGM load is reduced by ∼80 % compared to the commercial counterparts. These results provide confidence for the utilization of the RCT approach for the fabrication of robust nanostructured catalysts for next-generation, energy-efficient catalytic converters with improved performance at low and high temperatures and reduced costs. The RCT methodology is, in addition, highly generalizable, and can thus be applied for the design of a wide range of catalytic systems in the automotive sector and beyond. [ABSTRACT FROM AUTHOR]

Industrially, ultrafiltration (UF) membranes are produced through non-solvent induced phase separation (NIPS), but due to environmental hazards inherent to the NIPS process as well as the low surface porosity and fouling resistance of membranes produced via this method, an alternative route to UF membranes is desirable. This work presents the self-assembly of Pluronic block copolymers in the presence of water and a monomeric phase as a new technique for the preparation of UF membranes without the need for organic solvent or post-modification. Different compositions of block copolymer, water, and monomer were polymerized to obtain both hexagonal and lamellar mesostructures, as indicated by small angle X-ray scattering (SAXS) and cross-polarized light microscopy. As-synthesized membranes were found to have pore sizes in the range of 3–4 nm with a molecular weight cutoff of 1500 g/mol and displayed both excellent fouling resistance and high permeance of water, vastly outperforming a conventional NIPS UF membrane. Further, in contrast to NIPS, the proposed method provides flexibility in terms of both the final membrane chemistry and pore size. As such, it is a versatile approach that can be easily tailored to produce membranes for a wide range of applications including wastewater treatment and food processing. Image 1 • Block copolymer/water/oil mesophases can be used as templates for making membranes. • Membranes with ∼3–4 nm pore size can be made through mesophase-templating. • Mesophase-templated membranes have superior rejection compared to commercial ones. • Mesophase-templated membranes showed low flux decline in dead-end filtration. [ABSTRACT FROM AUTHOR]

Aerogels with chiral nematic structure are promising candidates for structural coatings and optical devices. Cellulose nanocrystals (CNCs) are excellent photonic building blocks for the fabrication of chiral nematic aerogels. Conventional bottom-up fabrication process usually is complicated, energy and time consumption. Herein, a simple method for fabricating CNCs and polyethylene glycol (PEG) based foams with chiral nematic structure was proposed. After CNCs-PEG based solid films were swollen with N-methylmorpholine N-oxide (NMMO) aqueous solutions, the obtained hydrogels were freeze-dried, resulting in chiral nematic foams. During the process, both macropores and mesopores were created with chiral nematic phase retained inside foam walls. Owning numerous macropores and chiral nematic walls of varying axial directions, the chiral nematic foams exhibited a broad-band reflection phenomenon. Moreover, the representative Titanium diisopropoxide(bis-2,4-pentanedionate) was permeated into foam walls, and transformed into chiral nematic TiO 2 foams after annealing. We envisage that the chiral nematic foams may have a promising application in the fields of chiral separation or chiral catalysis. A simple method is proposed to fabricate CNC-based foams with chiral nematic structure. CNC-based films are first swollen with a good solvent of cellulose. Then swollen CNC films are freeze-dried. The resultant chiral nematic foams exhibit a wide-band reflection phenomenon. Chiral nematic TiO 2 foams can be constructed by using CNC-based foams as a template. [Display omitted] • A simple method is proposed to fabricate cellulose nanocrystals (CNCs)-based foams with chiral nematic structure. • The obtained chiral nematic foams exhibit a wide-band reflection phenomenon. • Chiral nematic TiO 2 foams can be constructed by using CNCs-based foams as a template. [ABSTRACT FROM AUTHOR]

This paper describes the use of microtubules (MTs) as nanoscale templates for the biologically directed growth and assembly of cadmium sulfide (CdS) nanotubes. CdS is a wide bandgap semiconductor with valuable optical, electronic, and chemical properties, and the organization of CdS nanostructures is critical to their widespread utility. The present work explores a bioinspired, biomediated approach to the formation and assembly of CdS nanotubes. In particular, a biomimetic synthetic strategy is used to control the uniform growth of cubic zinc blende CdS nanocrystals on MT templates, replicating the MTs' tubular morphology with dense CdS only a single nanocrystal thick. Furthermore, specific interactions between MTs and functional microtubule-associated proteins (MAPs) are exploited to manipulate the secondary organization of these MT templates. The subsequent directed growth of CdS nanotubes on these structures produces specific biomediated architectures including linear arrays, 3D asters, and rings. Finally, cathodoluminescence from MT-templated CdS structures verifies that the valuable semiconducting character of these materials is exhibited. These demonstrations of nanoscale materials synthesis and assembly illustrate a new level of complexity and control over materials synthesis that may be achieved using such biological tools and processes. [ABSTRACT FROM AUTHOR]

Highlights: [•] Mixed sugar-based and cationic surfactants used to create mesoporous titanosilicate thin films. [•] Complexation between titanium precursor and maltoside headgroup promotes uniform titanium incorporation. [•] High level of isolated tetracoordinated titanium sites demonstrated by UV/vis spectroscopy. [•] Pm3n pore structure found in films, which should be accessible for adsorption and catalysis. [Copyright &y& Elsevier]

Highlights: [•] 2D functional molecular nanoarchitectures fabricated via self-assembly are reviewed. [•] The STM+XS approach combines scanning tunneling microscopy and X-ray spectroscopy. [•] The complementary approach comprehensively charactarizes the complex nanosystems. [•] Supramolecular construction principles and architecture functionality are discussed. [•] The aptitude of STM+XS for the field of on-surface covalent synthesis is addressed. [ABSTRACT FROM AUTHOR]

Highlights: [•] Binary colloidal arrays are fabricated by a simple self-assembly technology. [•] Fluoropolymer hierarchical arrays are templated from the binary colloidal arrays. [•] Both arrays are superhydrophobic with large water contact angles. [ABSTRACT FROM AUTHOR]

Highlights: [•] The silica-pillared α-ZrP is synthesized by interlayered templating method. [•] The silica-pillared α-ZrP has highly ordered interlayered mesoporous structure. [•] The self-assembly mechanism of mesostructured silica-pillared α-ZrP is proposed. [•] The silica-pillared α-ZrP establishes brilliant catalytic properties. [ABSTRACT FROM AUTHOR]

Abstract: Alumina materials with ordered mesostructure and hierarchical porosity have been synthesized via a one-step process using aluminum iso-propoxide as an inorganic precursor, pluronic P123 as a template, hydrochloric acid and citric acid as the pH adjustors, and 1,3,5-trimethylbenzene (TMB) as a swelling agent. These mesoporous aluminas have relatively high surface areas (up to 309m2/g), pore volumes (∼0.51cm3/g), large pore sizes (up to 7.5nm), and high thermal stability (up to 900°C). In addition, the weight ratios of TMB/P123 play an important role in the synthesis process for controlling the mesostructures and pore sizes of the materials. The alumina with highly ordered 2-D hexagonal mesostructure (space group p6mm) can be synthesized with the weight ratios of TMB/P123 ranging from 0 to 3. Simultaneously, the pore sizes of ordered mesoporous aluminas were gradually enlarged with the increase of the TMB content. However, phase transformation of the mesoporous alumina from the 2-D hexagonal to hierarchical could be realized when the TMB/P123 weight ratio was increased to 5. [Copyright &y& Elsevier]

Abstract: The morphologies that block polymers exhibit under various types of confinement are reviewed with emphasis on experimental results and theoretical predictions. Confining geometries in all three dimensions are considered and special attention is paid to cylindrical and spherical boundary conditions. Past experimental techniques and theoretical understanding are discussed and an outlook for future advances due to the possibility for novel, well ordered and aligned morphologies to occur when polymers are confined between surfaces of varying distance, curvature, and surface chemistry is provided. Confinement creates new morphologies which are not present in the bulk, indicating that the confined thermodynamic boundary conditions result in phase behavior that is distinct from the bulk and that there is the possibility for new phases and order-order transitions to be discovered as future researchers impose new types of confinement and explore a greater range of block polymer architecture, composition and molecular weights. The article concludes with a brief introduction of interference lithography, which can be used to form arbitrary and novel boundary conditions, and a perspective on the future outlook of the phase behavior of confined block polymers. [Copyright &y& Elsevier]

Abstract: Mesoporous alumina particles with spherical shape were prepared by spray pyrolysis of Al(NO3)2·9H2O precursor. The surface area and the mesopores structure were investigated with varying the concentration of surfactant (cetyltrimethylammonium bromide, CTAB) and urea. The surface area and pore volume of alumina particles prepared by spray pyrolysis was greatly influenced by the CTAB/Al ratio, whereas, no significant change in the average pore size (3±0.2nm) was observed. According to the small-angle X-ray spectrum (SAXS) analysis, the prepared alumina had warm-like mesostructure. The d-spacing was slightly changed with varying the CTAB/Al ratio and correlated to the BET surface area and the number of CTAB micelles involved in making mesopores. It was found that the use of urea additive in the spray solution is helpful to increase the surface of alumina particles as well as the SAXS peak intensity due to the formation of mesostructures. In terms of the surface area and the pore regularity, the optimal CTAB/Al ratio and urea concentration was 0.1 and 3.0M, respectively. [Copyright &y& Elsevier]

Abstract: Ordered nitrogen-containing mesoporous carbonaceous polymers have been synthesized via a direct triblock-copolymer-templating process by using soluble, low-molecular-weight urea–phenol–formaldehyde (UPF) resin as an organic precursor and amphiphilic triblock copolymer Pluronic F127 as a template. Characterization using small-angle X-ray scattering (SAXS), N2 sorption, transmission electron microscopy (TEM), elemental analysis, thermogravimetric analysis (TG), Fourier transform infrared (FTIR), and water adsorption techniques reveals that the obtained nitrogen-containing mesoporous polymers possess ordered structures, high surface areas (385–420 m2/g), large pore sizes (3.1–3.6nm) and pore volumes (0.25–0.44cm3/g), and high nitrogen content (2.69–2.94%). Various mesostructures, such as two-dimensional (2-D) hexagonal (space group, p6mm) and 3-D body-centered cubic (Im m) symmetries, can be obtained by simply adjusting the mass ratio of UPF/F127. The content of nitrogen in the mesoporous polymers can also be easy varied by changing the amount of urea and the reaction time of UPF resin precursors. Compared with the nitrogen-free mesoporous polymer, the obtained mesoporous carbonaceous polymers show a more hydrophilic nature and thus evidently higher water adsorption capacity. The presence of nitrogen groups can also significantly improve the adsorption performance of Fe(III) ions. [Copyright &y& Elsevier]

Abstract: Self-assembled nonionic alkyl glycoside surfactants are of interest for creating functional adsorption and catalytic sites at the surface of mesoporous sol–gel-derived materials, but they typically impart poor long-range order when they are used as pore templates. Improved order and control over the functional site density can be achieved by mixing the alkyl polyglycoside surfactant with a cationic surfactant. Here, we investigate the rarely reported lyotropic liquid crystalline (LLC) phase behavior of aqueous solutions of a nonionic disaccharide surfactant, n-dodecyl-β-d-maltoside (C12G2/DM), and cetyltrimethylammonium bromide (C16TAB) by low-angle powder X-ray diffraction (XRD) and polarized optical microscopy (POM). An approximate ternary phase diagram of the C16TAB–C12G2–water system is developed at 50°C, which includes 2-D hexagonal (P6mm symmetry), bicontinuous cubic (Iad symmetry), lamellar, and rectangular (cmm symmetry) LLC phases. By replacing the volume of water in the phase diagram with an equivalent volume of silica, ordered mesoporous materials are prepared by a nanocasting technique with variable C12G2/C16TAB ratios. For large regions of the phase diagram, this approach is predictive. However, silica materials synthesized with comparatively high C12G2/C16TAB ratios are only poorly ordered in a way that does not correspond to their lyotropic liquid crystalline phase behavior. Also, in contrast with our previous study of mixed C16TAB/n-octyl-b-d-glucopyranoside templating the boundary between hexagonal and bicontinuous cubic materials is shifted towards higher surfactant content than in the aqueous LLC system. [Copyright &y& Elsevier]

A simple strategy for the synthesis of macro-mesoporous carbonaceous monolith materials has been demonstrated through an organic-organic self-assembly at the interface of an organic scaffold such as polyurethane (PU) foam. Hierarchically porous carbonaceous monoliths with cubic ( Im $$ \bar 3 $$ m) or hexagonal ( p6mm) mesostructure were prepared through evaporation induced self-assembly of the mesostructure on the three-dimensional (3-D) interconnecting struts of the PU foam scaffold. The preparation was carried out by using phenol/formaldehyde resol as a carbon precursor, triblock copolymer F127 as a template for the mesostructure and PU foam as a sacrificial monolithic scaffold. Their hierarchical pore system was macroscopically fabricated with cable-like mesostructured carbonaceous struts. The carbonaceous monoliths exhibit macropores of diameter 100–450 μm, adjustable uniform mesopores (3.8–7.5 nm), high surface areas (200–870 m2/g), and large pore volumes (0.17–0.58) cm3/g. Compared with the corresponding evaporation induced self-assembly (EISA) process on a planar substrate, this facile process is a time-saving, labor-saving, space-saving, and highly efficient pathway for mass production of ordered mesoporous materials. [ABSTRACT FROM AUTHOR]

Abstract: n-Octyl-β-d-glucopyranoside (C8G1) has the potential to serve as a functional, nonionic template for mesoporous oxides, but its use has been limited due to its propensity to form lamellar mesostructures. Here, 2D hexagonal-structured mesoporous silicas with variable pore sizes are synthesized with C8G1 by the “nanocasting” technique (polycondensation of tetramethoxysilane in concentrated acidic solutions with evaporation) by mixing it with cetyltrimethylammonium bromide (CTAB) to promote ordering. In an effort to stabilize the silica network structure, a mild treatment with ammonia vapor at 50°C is introduced. Without ammonia treatment, the pore diameter remains constant as the C8G1:CTAB weight ratio increases even up to 0.3:1. When the as-made materials are treated with ammonia vapor, the degree of long-range order of the samples increases, and pore expansion is observed which increases in magnitude as the C8G1 content increases. Large degrees of expansion increase pore size fluctuations but do not eliminate long-range order. Materials with well-ordered, uniform pores can be made with C8G1/CTAB mixtures by limiting the amount of ammonia or increasing the amount of silica precursor. A mechanistic study suggests that micelle swelling occurs with CTAB, but is limited by increased polycondensation of silica and favorable headgroup–silica interactions. With the glucopyranoside surfactant, the extent of expansion is greater not only because of a change in the physical interaction with silica, but also because the Maillard reaction occurs under surprisingly mild conditions. [Copyright &y& Elsevier]

Polymeric systems have played important roles as templates for nanofabrication since they can offer nanotemplates with different morphologies and tunable sizes, can be easily removed after reactions, and can be further modified with different functional groups to enhance the interactions. This review covers recent advances in polymer-assisted fabrication of nanomaterials with emphasis on ordered polymeric nanostructures. Examples could include self-assembled amphiphilic block co-polymers/surfactants, cross-linkable polymers, dendrimers, microemulsions, latex particles, biomacromolecules, electric- or shear-induced structures as templates to fabricate inorganic, organic/inorganic composites and polymeric materials with nanoscale modifications. The phase behavior of block co-polymers in water and the use of templates to form ordered nanostructures are reviewed in detail. Modern physical techniques for nanoscale characterization are briefly discussed. [Copyright &y& Elsevier]

The paper reviews the use of surfactant self-assembly to template the synthesis of polymers, ceramics with extended structures, and nanoparticles. The objective of the review is to highlight newer concepts linking self-assembly to materials nanostructure and to the realization of functional materials. [Copyright &y& Elsevier]

In the last two decades the study of the properties of biological self‐organization has created a separate area of research, ranging from biomedicine and biotechnology to materials science and nanotechnology. In particular, the design of self‐assembling protein and peptide building blocks is often achieved by drawing inspiration from natural fibrous proteins such as collagen, elastin, silk, and spider silks that are built up from repetitive sequences. Self‐assembling proteins and peptides are water soluble and biocompatible nanostructures formed spontaneously under mild conditions through non‐covalent interactions. They form supramolecular structures such as ribbons, nanotubes, and fibers. The wide range of chemical functionalities found in peptides (i.e., 20 amino acids) enables the design and engineering of specific interactions with target materials for potential technological applications. Moreover, with the aid of computational methods, tailor made modifications can be inserted for the «on‐demand» design of functional amyloid materials binding to ions or compounds. Technologically, the self‐organized structures can be used as templates for the growth of inorganic materials, such as metallic nanoparticles (silver, gold, and platinum), silica, calcium phosphates etc. Self‐assembling peptides may also create hydrogels and entangled fibrous networks that can be used as scaffolds for attachment, growth and proliferation of living cells, allowing tissue repair and engineering. In this short review we summarize the progress made in the field with emphasis on our progress on how to translate fundamental structural knowledge from the adenovirus fiber protein into self‐assembling nanomaterials targeted for novel applications. [ABSTRACT FROM AUTHOR]

The cover image presents an artificially colored transmission electron micrograph of cadmium sulfide (CdS) nanocrystals templated on a protein microtubule (MT). This image is superimposed on a colorful brightfield image of MT‐templated CdS nanostructures bound to a silicon substrate. In the article on page 863, E. D. Spoerke and co‐workers discuss how biomediated, in vitro assembly of the MT templates to form arrays, rings, and asters facilitates the growth of complex semiconducting CdS nanostructures. [ABSTRACT FROM AUTHOR]