Green and facile edge-oxidation of multi-layer graphene by sodium persulfate activated with ferrous ions

Effective edge oxidation of graphene with high structural integrity is highly desirable yet technically challenging for most practical applications. In this work, we have developed a green and facile strategy to obtain edge-oxidized graphene with good dispersion stability and high electrical conductivity by exploiting high edge reactivity of highly conductive multi-layer graphene and oxidizing radicals (SO₄⁻˙) generated from sodium persulfate (Na₂S₂O₈) with ferrous ion (Fe²⁺) activation. Owing to high structural integrity of pristine graphene and effective edge oxidation, the obtained edge-oxidized graphene exhibited excellent dispersion stability and satisfactory electrical conductivity (i.e. ≥240 S cm⁻¹). Moreover, the oxidation degree of pristine graphene can be well controlled by adjusting treatment time. The obtained edge-oxidized graphene is expected to find a variety of applications in many fields of anti-static films, energy storage materials, flexible sensors and high-performance nanocomposites.

A green and facile strategy is represented to obtain edge-oxidized graphene by exploiting sulfate radicals generated from Na₂S₂O₈ with Fe²⁺ activation.     

A new self-designed “tongue root holder” device to aid fiberoptic intubation

Objective

In this study, we aimed to assess the feasibility of fiberoptic intubation (FOI), using a new, self-designed, “tongue root holder” device, in combination with the jaw thrust maneuver.

Methods

Three hundred patients undergoing elective surgery requiring orotracheal intubation were enrolled. Patients presented at least one or more risk factors for difficult airway. The patients were randomly allocated at a 1:1 ratio to one of two groups: group L, FOI with tongue root holder, or group C, standard FOI. Orotracheal FOI was performed after commencement of anesthesia. The jaw thrust maneuver was applied in both groups to facilitate advancement of the fiberoptic bronchoscope. The primary endpoint was the feasibility of FOI. The secondary endpoints were number of attempts, time to intubation, and airway clearance at the soft palate and epiglottis levels.

Results

The FOI was achieved in all 150 patients in group L, significantly higher than that in group C (100% vs 95.3%; P = 0.015). Less attempts of intubation were made in group L (P = 0.039). Mean time to successful intubation on the first attempt was shorter in group L (P < 0.001). The mean times to view the vocal cord and carina were also shorter in group L (P = 0.011 and P < 0.001, respectively). Airway clearance was better in group L at both the soft palate and the glottis levels (P = 0.010 and P = 0.038, respectively).

Conclusions

This study shows that FOI is feasible with the newly introduced, self-designed, “tongue root holder” device, when combined with the jaw thrust maneuver in patients with risk factors for difficult airway. The device also provides better airway clearance, less intubation attempts, and shorter time to intubation at first attempt.

Clinical relevance

Fiberoptic bronchoscope has been the gold standard for routine management of difficult airway. A technique to open the airway is introduced to reduce the incidence rate of upper airway obstruction.

     

成年健康女性外周血免疫相关指标的分析

目的 探讨成年健康女性外周血中多项免疫相关指标合适的参考范围和临床价值.方法 采集21～40岁的356例成年健康女性外周血,测定血常规、T淋巴细胞亚群、自然杀伤(NK)细胞和B细胞的数量及百分比,采用免疫比浊法对免疫球蛋白(Ig)进行分析,采用95％ 置信区间表示各指标参考范围.结果 21～40岁成年健康女性白细胞计数的参考范围为(3.71～9.47)×109/L;CD3+CD4+绝对数参考范围为378.21～1170.02个/微升,百分比参考范围为23.73％ ～51.05％;NK细胞数参考范围为94.4～660.4个/微升;IgA、IgG、IgM的参考范围分别为1.10～4.01 g/L、9.51～15.80 g/L和0.64～2.57 g/L.结论 该研究全面评估了成年健康女性外周血免疫相关指标的均数和中位数,为基础研究和临床实验提供了较为规范的反映成年健康女性身体免疫状况的参考范围.     

Facile construction of Fe,N and P co-doped carbon spheres by carbothermal strategy for the adsorption and reduction of U(vi)

In this work, nitrogen and phosphorus co-doped magnetic carbon spheres encapsulating well-dispersed active Fe nanocrystals (Fe/P-CN) were fabricated via a simple copolymer pyrolysis strategy. Benefiting from heteroatoms doping, Fe/P-CN could primarily adsorb soluble U(vi) ions through abundant functional groups, and subsequently, the adsorbed U(vi) could be reduced to insoluble U(iv) by Fe nanocrystals. Fe/P-CN pyrolyzed at 800 °C (Fe/P-CN-800) exhibited excellent U(vi) removal capacity of 306.76 mg g⁻¹, surpassing nitrogen and phosphorus co-doped carbon spheres and nano zero-valent iron. In addition, the magnetic separation and thermal reactivation properties endow Fe/P-CN-800 with excellent reusability. This research, especially, provides a promising synergistic adsorption and reduction strategy to effectively remove U(vi) using heteroatom-doped composites.

The constructed novel magnetic carbon sphere co-doped by N, P, Fe (Fe/P-CN) exhibits high U(vi) removal efficiency, excellent magnetic separation and reusability, evidencing the potential practical applications in environmental remediation.     

From “S” to “O”: experimental and theoretical insights into the atmospheric degradation mechanism of dithiophosphinic acids

Dithiophosphinic acids (DPAHs, expressed as R₁R₂PSSH) are a type of sulfur-donor ligand that have been vastly applied in hydrometallurgy. In particular, DPAHs have shown great potential in highly efficient trivalent actinide/lanthanide separation, which is one of the most challenging tasks in separation science and is of great importance for the development of an advanced fuel cycle in nuclear industry. However, DPAHs have been found liable to undergo oxidative degradation in the air, leading to significant reduction in the selectivity of actinide/lanthanide separation. In this work, the atmospheric degradation of five representative DPAH ligands was investigated for the first time over a sufficiently long period (180 days). The oxidative degradation process of DPAHs elucidated by ESI-MS, ³¹P NMR, and FT-IR analyses is R₁R₂PSSH → R₁R₂PSOH → R₁R₂POOH → R₁R₂POO–OOPR₁R₂, R₁R₂PSSH → R₁R₂PSS–SSPR₁R₂, and R₁R₂PSSH → R₁R₂PSOH → R₁R₂POS–SOPR₁R₂. Meanwhile, the determination of pK_a values through pH titration and oxidation product by PXRD further confirms the S → O transformation in the process of DPAH deterioration. DFT calculations suggest that the hydroxyl radical plays the dominant role in the oxidation process of DPAHs and the order in which the oxidation products formed is closely related to the reaction energy barrier. Moreover, nickel salts of DPAHs have shown much higher chemical stability than DPAHs, which was also elaborated through molecular orbital (MO) and adaptive natural density portioning (AdNDP) analyses. This work unambiguously reveals the atmospheric degradation mechanism of DPAHs through both experimental and theoretical approaches. At the application level, the results not only provide an effective way to preserve DPAHs but could also guide the design of more stable sulfur-donor ligands in the future.

The oxidation behavior and mechanism of five typical DPAH ligands in the air was systematically studied through experimental and theoretical methods.     

Improved food additive analysis by ever-increasing nanotechnology

Improper use of food additives may lead to potential threat to human health, making it important to develop sensitive and selective method for their detection. Nanomaterials with unique chemical and electrochemical properties show extensive applications in the design of food additive sensing systems. In this review, we summarize the recently adopted electrochemical and optical analysis of food additives based on nanomaterials. Detection of typical food additives (colorants and preservatives) by using different sensing mechanisms and strategies are provided. In addition, determination of illegal food additives is also briefly introduced. Finally, this review highlights the challenges and future trend of nanomaterial-based food analysis system.     

甲下穿刺治疗甲下血肿 51例

目的介绍一种穿刺引流治疗甲下血肿方法,并分析其治疗效果。方法选取 2015年 3月至 2018年 3月苏州明基医院甲下血肿病人 51例,用 5 mL无菌注射器针头,于病指(趾)尖末端进针,挤压,穿刺引流,观察症状缓解情况。结果 51例疼痛及肿胀即刻缓解,术后随访 1周,无感染及复发。结论甲下穿刺治疗甲下血肿操作简单,安全性高,是一种行之有效的方法。     

Masthead,Volume 73, Issue 1

This review provides a summary statement of recommended implementations of arterial spin labeling (ASL) for clinical applications. It is a consensus of the ISMRM Perfusion Study Group and the European ASL in Dementia consortium, both of whom met to reach this consensus in October 2012 in Amsterdam. Although ASL continues to undergo rapid technical development, we believe that current ASL methods are robust and ready to provide useful clinical information, and that a consensus statement on recommended implementations will help the clinical community to adopt a standardized approach. In this review, we describe the major considerations and trade‐offs in implementing an ASL protocol and provide specific recommendations for a standard approach. Our conclusion is that as an optimal default implementation, we recommend pseudo‐continuous labeling, background suppression, a segmented three‐dimensional readout without vascular crushing gradients, and calculation and presentation of both label/control difference images and cerebral blood flow in absolute units using a simplified model. Magn Reson Med 73:102–116, 2015. © 2014 Wiley Periodicals, Inc.