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This paper examines the rise and fall of the Administrative Bureau of Prohibited Drugs in 1920s Shanghai. It identifies the factors associated with the endeavours of the central government to experiment with establishing a Bureau dedicated to regulating refined drugs and the reasons why the Bureau operated for just about two years. It argues that the concerns regarding the widespread of refined drugs and the expected profits of regulating the business pushed the central government to experiment establishing the Bureau. Moreover, this experiment was a tool with which the Beiyang government aimed to centralise its authorities on the issue of drug control. However, the room for manoeuvring the Bureau was limited, mainly because of the resilience of the drug economy and the politicised regulations. Struggling in the narrow space between the colonial powers, the merchant groups, and the local authorities acting under the influence of warlords, the Bureau was doomed to be short-lived. Its history reveals the resilience of both licit and illicit drug economy and the power struggles that resulted from efforts to regulate refined drugs. [ABSTRACT FROM AUTHOR]

The ranging accuracy of pulsed time-of-flight (TOF) lidar is affected by walk error and jitter error. To solve the issue, the balanced detection method (BDM) based on fiber delay optic lines (FDOL) is proposed. The experiments are carried out to prove the performance improvement of BDM over the conventional single photodiode method (SPM). The experimental results show that BDM can suppress common mode noise and simultaneously shift the signal to high frequency, which reduces the jitter error by approximately 52.4% and maintains the walk error at less than 300 ps with a non-distorted waveform. The BDM can be further applied to silicon photomultipliers. [ABSTRACT FROM AUTHOR]

This study investigates the potential of Tin Slag Polymer Concrete (TSPC) strengthening through confinement using basalt fiber reinforced polymer (BFRP) and aramid fiber reinforced polymer AFRP) confinement. TSPC short cylindrical column samples have been wrapped with BFRP and AFRP in a single layer (30 mm overlap) using Sikadur-330 epoxy and final samples were coded as TSPC-UC, TSPC-BF and TSPC-AF for unconfined, BFRP and AFRP for confined respectively. After curing for 30 days at room temperature, compressive test has been performed to know the strength, modulus, strain, fracture energy and failure modes of unconfined and confined TSPC. Test result shows that AFRP confinement (114.24 MPa) provide more upsurge in strength enhancement compared to BFRP (81.52 MPa). Fracture energy value of TSPC-AF (821.18 J) is higher than TSPC-BF (538.66 J), but compressive modulus of TSPC-AF (3.23 GPa) is lower than TSPC-BF (4.32 GPa). In addition, yield stress value of TSPC-AF (80.71 MPa) is higher than TSPC-BF (57.21 MPa). Moreover, stress-strain curve and failure mode has shown that TSPC-AF exhibit higher degree of brittleness compared to TSPC-BF. Finally, it is noticed that there are some similarities in strength augmentation of TSPC amid BFRP and glass fiber reinforced polymer (GFRP) as well as between AFRP and carbon fiber reinforced polymer (CFRP) confinement. [ABSTRACT FROM AUTHOR]

Natural fibers (NFs) and inorganic particles have been successfully grown in the polymer to enhance its properties. The basalt fiber (BF) and modified hydrotalcite (LDHs) reinforced epoxy resin matrix composites were prepared, and the effects of fiber and modified hydrotalcite (G‐LDHs) on the microstructural characteristics of composites were investigated. Fourier transform infrared spectroscopy and X‐ray diffraction were respectively used to analyze the structure of modified BF and G‐LDHs, and thermogravimetric analysis was performed to study thermal stability. The mechanical properties of composites, including dynamic thermomechanical and tensile and flexural properties, were respectively studied by dynamic mechanical analysis (DMA) and universal testing machine. Experimental results show the successful synthesis of high‐performance epoxy copolymers. The impact strength, tensile strength, and elastic modulus of EP/BF/G‐LDHs respectively reached 7.07 kJ/m2, 20.52 MPa, and 2595 MPa when the content ratio of BF to hydrotalcite in the additive was 3:3. The DMA test showed that the glass transition temperature (Tg) value increased by 18.3°C, and the thermal stability of composite materials was improved. The storage modulus E′ value increased by 268.04 MPa, and the stiffness of the epoxy material and the mechanical properties were also elevated. The TGA and DTG curves indicate that the cured composites also exhibit excellent thermal stability. The effect of g‐LDHS particle size on the properties of composites was also discussed. Overall, the synergistic and complementary enhancement effect of the two materials is the best when the diameter of hydrotalcite is similar to that of BF, and the performance of the composite material is considerably improved. [ABSTRACT FROM AUTHOR]