of the 2D structures has approached its limit (< 90%) due to which the energy loss via reflection (2-5%) and thermal radiation heat loss (8-12%) occurs in all the 2D structures.One of the effective strategies for further improving the vapor-generation efficiency is to decrease the surface temperature of the absorber by increasing the surface area within a given projection area. [22] Some unprecedented vapor-generation rates have been reported in various 3D generators, which are all beyond the input solar energy limit. [23][24][25] Here, we have found that bamboos, as a natural hierarchical cellular material, can be excellent 3D solar vapor-generation devices due to their unique structural features. By a simple carbonization progress, the bamboos maintain remarkable mechanical property. Meanwhile, the carbonized bamboo-based evaporator possesses the following advantages: 1) natural hydrophilicity; 2) numerous aligned microchannels acting as highways for rapid water transport; 3) high light absorptance in a broad spectral range; 4) reduced thermal radiation heat loss; 5) lower average temperature than environment; 6) reduced vaporization enthalpy of water confined in the bamboo mesh; 7) remarkable mechanical properties; 8) ability of salt self-cleaning; 9) good scalability and low cost. As a result, a floating carbonized bamboo sample can evaporate water with an extremely high vapor-generation rate of 3.13 kg m −2 h −1 under 1 sun illumination. It also shows superior reusability and stability for solar vapor generation, without any performance degradation after cycling 360 h. The carbonized bamboo shows favorable overall performance compared with other reported solar vapor generators and has attractive applications in desalination as well asindustrial and domestic wastewater abatement. All of these features are elucidated below in detail.Bamboo is the fastest-growing and highest-yielding hierarchical cellular material on the Earth. A typical bamboo reaches maturity within months and ultimate mechanical properties within few years, making it one of the most renewable resources. [26] Figure 1a-c shows the illustration of the design concept for a bamboo-based solar vapor-generation device. Bamboo tubes with desired height were cut from the natural bamboo and were carbonized to make it dark. The carbonized Given the global challenges of water scarcity, solar-driven vapor generation has become a renewed topic as an energy-efficient way for clean water production. Here, it is revealed that bamboo, as a natural hierarchical cellular material, can be an excellent 3D solar vapor-generation device by a simple carbonization progress. A floating carbonized bamboo sample evaporates water with an extremely high vapor-generation rate of 3.13 kg m −2 h −1 under 1 sun illumination. The high evaporation rate is achieved by the unique natural structure of bamboos. The inner wall of bamboo recovers the diffuse light energy and the thermal radiation heat loss from the 3D bamboo bottom, and the outer wall captures energy from the warmer...

Anti-washout-type calcium phosphate cement (aw-CPC) was prepared by introducing chitosan, sodium alginate, or modified starch into the powder phase of CPC, respectively. The results showed that these cements cannot be washed out and set within approximately 10-30 min even if the pastes were immersed in distilled water immediately and were shaken in a shaker after mixing and moulding. To our knowledge, it is the first report about the influence of the content of these anti-washout additives on the rheological properties and injectability of the cement. Moreover, novel approach of yield stress measurement was used to evaluate the injectability of the pastes. A modified starch was originally used as anti-washout agent for CPC. This study provided a convenient way to use the injectable CPC with good anti-washout performance when the paste was exposed to blood. The aw-CPC had potential prospects for the wider applications in surgery such as orthopaedics, oral, and maxillofacial surgery.

An injectable calcium phosphate bone substitute material has been prepared by mixing amorphous calcium phosphate (ACP) and dicalcium phosphate dihydrate (DCPD) for use in noninvasive surgery, and the influence of additives, such as disodium hydrogen phosphate, polyethylene glycol (PEG), glycerin, and citric acid, on the rheological properties and injectability of the ACP + DCPD cement system have been studied in this work. Novel approach of thixotropy measurement has been used to characterize the stability of the pastes. The results show that the injectability and the setting time can be augmented by the addition of disodium phosphate solution to the paste but reduced by the addition of PEG 200, glycerin, or citric acid to the paste. This study suggests that the injectability and the setting time of the ACP + DCPD bone substitute material can be balanced, and the injectable calcium phosphate bone substitute material with satisfied fluidity and injectability for clinical operation can be prepared by optimizing the additives and their concentrations, according to different clinical requirements.

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