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Scientific scandals are catalysts for the evolution process of legal governance. The 2018 CRISPR-babies Incident has essentially triggered China's legal reforms of ethics governance in science and technology. This paper explores the institutional deficiency that led to such a scandal, analyzes its long-term implications for legal governance, and presents China's recent legal progress in response to such an issue. The rapid legislative response to the CRISPR-babies Incident is a double-edged sword, while promoting the improvement of the legal system, it can also cause issues like fragmentation of governance, contradictory rules, and conflict of interest. China should integrate departmental norms and upgrade its level of effectiveness. Strengthening legislation is the implementation path, and improving ethical review, supervision and scientific research integrity systems are the crucial means. In addition, it is necessary to bring the coordinating function of the Central Science and Technology Commission into full play and pay more attention to public engagement and international cooperation.

Generally, injecting activated carbon in front of an air preheater is a common method for removing mercury in coal-fired power plants. However, high cost and low efficiency limit the practical application of this procedure. As one of the transition metal dihalides, molybdenum disulfide (MoS2) has attracted much attention. Herein, density functional theory calculation was applied to explore the mercury removal properties of MoS2 due to its good affinity for mercury. MoS2 was prepared using hydrothermal methods, while MoS2 doped with MnO2 (Mm adsorbent) was prepared using an ultrasonic mixing method. The prepared Mm adsorbent was characterized using X-ray diffraction, scanning electron microscopy (SEM), transmission electron microscopy (TEM),and X-ray photoelectron spectroscopy. Rod-shaped MnO2 successfully appeared on the surface of flower-shaped MoS2. The adsorption of mercury (Hg0) on the MoS2/MnO2 (Mm) surface matched the Mars–van Krevelen reaction mechanism, indicating the consumption of lattice oxygen in the adsorbent. Additionally, the mercury removal efficiency of 3-Mm (MoS2 doped with 30 wt. % MnO2) adsorbent can still reach 90% under N2 + 200 ppm SO2.

With the increasing use of renewables in energy systems, grid stability becomes a major issue due to the intermittent nature of energy sources such as solar and wind. To compensate for the unstable renewable energy sources, storage technologies have been regarded as effective methods. Liquid air energy storage (LAES) has gained wide attention due to its inherent advantages: geographically unconstrained and high energy density. This work presents a techno-economic analysis of an LAES system with a storage capacity of 10 MW / 80 MWh. Three different layouts of the LAES are evaluated and compared based on net present value (NPV) and payback period. The economic results show that the LAES system with a 2-stage compressor and a 3-stage expander (Case 1) has the largest NPV of 918.1 M$, which is 33.7 % and 10.7 % larger than a system with a 4-stage compressor and a 4-stage expander without (Case 2) / and with (Case 3) an additional Organic Rankine Cycle (ORC). In addition, the shortest payback period of 6.2 y is obtained in Case 1 compared to 6.9 and 6.4 y for Cases 2 and 3. This means that Case 1 is the most profitable layout for the studied LAES systems.

With the penetration of renewable energy sources into the energy market, an emerging problem is the energy stability during energy supply and delivery. Energy storage technologies have the ability to overcome the intermittent nature of energy sources (such as wind and solar energy) and respond to unexpected situations like power failure. Liquid air energy storage (LAES) achieves good round-trip efficiencies by using hot and cold energy storages for heat transfer between the charging and discharging operations. In this work, the LAES technology has been studied and multi-component fluid cycles (MCFCs) are considered for the first time to replace the previously suggested single-component fluids in the cold thermal energy storage cycles to increase the performance of the cold cycles. Two case studies related to single MCFC and dual MCFC are simulated, optimized and compared. The optimal composition for the multi-component fluids is determined by using a particle swarm optimization (PSO) method. The objective function is to maximize the round-trip efficiency of the process. The results indicate that the LAES process with dual MCFC is superior to the case with single MCFC in terms of liquid yield (95.1 % vs. 87.1 %), exergy efficiency (86.1 % vs. 82.4 % for charging and 85.5 % vs. 78.5 % for discharging) and round-trip efficiency (61.8 % vs. 53.9 %).

In this paper, some means are proposed to improve the performances of the set-top box (STB) based media distribution schemes for IPTV. Firstly, the lightweight packet encryption is used to replace traditional complete encryption in order to reduce the time cost. Secondly, a method is introduced to form a unique customer code and generates a unique media copy for each customer in order to trace illegal redistributors. Thirdly, the desynchronization operations are introduced to make different copies in order to resist collusion attacks. Analyses and experiments show that the proposed packet encryption saves much time cost compared with traditional encryption and the saved time cost is enough for the added new operations. Additionally, the produced media copy is different from each other, and their collusion will generate a copy with much degradation, which can resist the content leakage from the gap between STB and TV set. [ABSTRACT FROM AUTHOR]

A scheme is proposed to implement commutative video encryption and watermarking during advanced video coding process. In H.264/AVC compression, the intra-prediction mode, motion vector difference and discrete cosine transform (DCT) coefficients' signs are encrypted, while DCT coefficients' amplitudes are watermarked adaptively. To avoid that the watermarking operation affects the decryption operation, a traditional watermarking algorithm is modified. The encryption and watermarking operations are commutative. Thus, the watermark can be extracted from the encrypted videos, and the encrypted videos can be re-watermarked. This scheme embeds the watermark without exposing video content's confidentiality, and provides a solution for signal processing in encrypted domain. Additionally, it increases the operation efficiency, since the encrypted video can be watermarked without decryption. These properties make the scheme a good choice for secure media transmission or distribution. [ABSTRACT FROM AUTHOR]

Advanced Video Coding is recently announced and widely used, although the according protection means have not been developed thoroughly. In this paper, a secure A VC coding scheme is presented based on some partial encryption algorithms. During A VC encoding, such sensitive data as intra-prediction mode, residue data and motion vector are encrypted partially. Among them, the intra-prediction mode is encrypted based on Exp-Golomb entropy coding, the intra-macroblocks' DCs are encrypted based on context- based adaptive variable length coding (CA VLC), and intra- macroblocks' ACs and the inter-macroblocks' MVDs are sign-encrypted with a stream cipher followed with variable-length coding. This encryption scheme is secure in perception, keeps format compliance, and obtains high time efficiency though reducing the encrypted data volumes. These properties make it practical to incorporate encryption/decryption process into compression/decompression process, and thus suitable for secure video transmission or sharing. [ABSTRACT FROM AUTHOR]