An actively compensated 8 nT-level magnetic shielding system for 10-m atom interferometer.

We design and develop a high-performance magnetic shielding system for a long baseline fountain-type atom interferometer. The shielding system is achieved by a combination of passive shielding using permalloy and active compensation with coils. An 11.4 m-long three-layer cylindrical shield is completed by the process of welding, local annealing, and entire annealing. The active compensations compress the residual magnetic field to 8.0 nT max-to-min and the corresponding gradient below 30 nT/m over 10 m along the axial direction in which external compensation, internal compensation, and constant magnetic field (C-field) compensation reduce the inhomogeneities to 25.0, 12.6, and 1.7 nT (standard deviation) sequentially. We estimate that this system could reduce the systematic error of the quadratic Zeeman shift to the 10-13 level for the weak equivalence principle test with a simultaneous 85Rb-87Rb dual-species atom interferometer.

GaOx@GaN Nanowire Arrays on Flexible Graphite Paper with Tunable Persistent Photoconductivity.

Flexible optoelectronic synaptic devices that functionally imitate the neural behavior with tunable optoelectronic characteristics are crucial to the development of advanced bioinspired neural networks. In this work, amorphous oxide-decorated GaN nanowire arrays (GaOx@GaN NWAs) are prepared on flexible graphite paper. A GaOx@GaN NWA-based flexible device has tunable persistent photoconductivity (PPC) and shows a conversible fast/slow decay process (SDP). Photoconductivity can be modulated by single or double light pulses with different illumination powers and biases. PPC gives rise to the high-performance SDP such as a long decay time of 2.3 × 105 s. The modulation mechanism is proposed and discussed. Our results reveal an innovative and efficient strategy to produce decorated NWAs on a flexible substrate with tunable optoelectronic properties and exhibit potential for flexible neuromorphic system applications.

Laser frequency shift up to 5 GHz with a high-efficiency 12-pass 350-MHz acousto-optic modulator.

We demonstrate a novel laser frequency shift scheme using a 12-pass 350-MHz acousto-optic modulator (AOM). This AOM system shows better performance compared to ordinary acousto-optic modulation schemes. The frequency of the incident laser beam is shifted by 4.2 GHz with the total diffraction efficiency as high as 11%, and the maximum frequency shift is 5 GHz. Combining the ±1st order diffraction, laser signals with up to 10 GHz frequency difference can be obtained, which fulfill most frequency shift requirements of laser cooling and coherent manipulation experiments with alkali metal atoms.

Effects of sulfated, phosphorylated and carboxymethylated modifications on the antioxidant activities in-vitro of polysaccharides sequentially extracted from Amana edulis.

In this study, four sequentially extracted polysaccharides (AEPs) from Amana edulis were modified by sulphation, phosphorylation, and carboxylation modifications (S-AEPs, P-AEPs, C-AEPs), and compared for their anti-oxidant activities. After modification, sugar and protein contents were decreased and uronic acid content was increased in comparison to native AEPs. UV absorption showed similar maximum absorption peaks of modified derivatives which indicated their homogeneous nature. FTIR spectra confirmed the conversion of hydroxyl groups to OS, COO, and POH bonds, respectively. The phosphorylated derivatives (P-AEPs) displayed the highest DPPH, hydroxyl radical, and ferrous ions radical scavenging abilities. Sulfated polysaccharides (S-AEPs) were observed with high reducing ability. The C-AEPs maintained the stable antioxidant properties after carboxylation modification. Our results indicated that the chemical modification of different polysaccharide components has significantly affected their antioxidant potential for their use in food industry and human health.

The rheological properties and emulsifying behavior of polysaccharides sequentially extracted from Amana edulis.

The rheological properties and emulsifying behavior of four polysaccharides (HBSS, CHSS, DASS, and CASS) sequentially extracted from Amana edulis (AEPs) were investigated under various concentrations, temperatures, pH levels, and ionic strengths. The apparent viscosity of the four AEPs solutions at 1% (w/w) concentration were found to be CHSS > DASS > HBSS > CASS. When the AEPs were heated to 100 οC, they showed lower colloidal viscosity, whereas after refrigeration and chilling, higher apparent viscosities were observed. The apparent viscosity of four AEPs at pH 10 or pH 4 was lower than that at pH 7. The apparent viscosity increased at a lower sodium ion concentration and then declined with an increase in ion concentration. The storage modulus (G') and loss modulus (G″) increased with an increase in oscillation frequency. The emulsifying activity and stability were enhanced as the concentration of the four AEPs increased. The emulsifying activity and stability of the AEPs were steady within the pH range of 2-10 and NaCl concentration range of 0-0.4 mol/L. Our results implied that these polysaccharides can be utilized as a novel hydrocolloid source for natural thickeners in the food industry.

Physicochemical and antioxidant potential of polysaccharides sequentially extracted from Amana edulis.

Amana edulis polysaccharides (AEPs) specifically HBSS, CHSS, DASS, and CASS were sequentially extracted with four different solvents. The present study characterized the AEPs with particular focus on their physicochemical and anti-oxidant based functional properties. Initially, monosaccharide analysis revealed arabinose (31.7%, 32.5%, 36.5%) as the main sugar in HBSS, CHSS, and DASS whereas, galactose (31.4%) in CASS besides their respective molecular weights of 6.29 × 102, 1.5 × 102, 8.1 × 102, and 2.6 × 103 kD. HBSS showed the maximum solubility, while, CASS was observed for higher foam capacity and foam stability. Among all the fractions, DASS was observed with higher thermal stability. HBSS showed the highest ABTS+ scavenging activity. HBSS and CASS had higher DPPH and OH- scavenging activities. DASS depicted the highest chelation and reducing ability. To summarize, these polysaccharides fractions may be further utilized for their enormous prospective in functional foods preparation.