Efficient Metal Recovery from Industrial Wastewater:Potential Oscillation and Turbulence Mode for Electrochemical System

Efficient metal recovery from industrial wastewater facilitates addressing of the environmental hazards and resource requirements of heavy metals.The conventional electrodeposition recovery method is hampered by the limitations of interfacial ion transport in charge-transfer reactions,creating challenges for simultaneous rapid and high-quality metal recovery.Therefore,we proposed integrating a transient electric field(TE)and swirling flow(SF)to synchronously enhance bulk mass transfer and promote interfacial ion transport.We investigated the effects of the operation mode,transient frequency,and flow rate on metal recovery,enabling determination of the optimal operating conditions for rapid and efficient sequential recovery of Cu in TE&SF mode.These conditions included low and high electric levels of 0 and 4 V,a 50%duty cycle,1 kHz frequency,and 400 L·h^(-1)flow rate.The kinetic coefficients of TE&SF electrodeposition were 3.5-4.3 and 1.37-1.97 times that of single TE and SF electrodeposition,respectively.Simulating the deposition process under TE and SF conditions confirmed the efficient concurrence of interfacial ion transport and charge transfer under TE and SF synergy,which achieved rapid and highquality metal recovery.Therefore,the combined deposition strategy is considered an effective technique for reducing metal pollution and promoting resource recycling.

1例EGFR L747S和L858R双突变肺腺癌患者的治疗

表皮生长因子受体(epidermal growth factor receptor,EGFR)突变中最常见的突变是外显子19缺失突变和外显子21 L858R突变,这两种突变都对EGFR酪氨酸激酶抑制剂(EGFR-tyrosine kinase inhibitors,EGFR-TKIs)有非常好的响应性。然而,EGFR-TKIs对罕见EGFR突变的疗效尚有争议。在治疗过程中,许多患者最终也会对EGFR-TKIs产生耐药性。此外,对于对奥希替尼产生耐药性的患者,特别是那些具有罕见或复杂突变的患者,仍然没有标准的治疗方案。本文介绍了1例具有EGFR L747S和L858R双突变的肺腺癌患者,该患者在出现奥希替尼耐药后接受帕博利珠单抗联合化疗治疗有效,且无疾病进展生存期为13个月。这是国内外首例在携带EGFR L747S和L858R双突变的肺腺癌患者对奥希替尼耐药之后使用帕博利珠单抗免疫治疗联合化疗的报道,本案例可为具有类似罕见突变患者的治疗提供参考。

构建Cu台阶位促进电催化CO_(2)还原制醇类化学品的研究

电催化CO_(2)制备高附加值的化学品是解决当前碳排放问题的可行技术路线之一.其中,合成醇类化合物因具有广泛用途和高价值而备受关注.在电催化CO_(2)还原合成多碳醇反应中,关键中间体*CH_(2)CHO容易发生热力学有利的脱氧反应而生成C2H4,降低了醇类产物的选择性.由于电催化CO_(2)还原是一个表面结构敏感的反应,因此可以通过设计Cu基催化剂的特定表面结构,实现对反应路径的有效调节,从而提升醇类产物的选择性.本课题组前期通过密度泛函理论(DFT)计算和主成分分析法等对Cu基催化剂的构效关系进行解析,说明配位不饱和的台阶位点有望高效地促进醇类产物的生成.本文进一步从实验角度,证明了配位不饱和的台阶位点是生成醇类产物的活性位点.本文采用CO分子作为还原剂制备了CuO衍生的金属Cu催化剂(COD-Cu),利用CO分子对Cu表面的重构作用,获得了具有丰富台阶位点的Cu催化剂.而通过H_(2)还原制备的金属Cu催化剂(HOD-Cu)对照样表面则多为平面位点.X射线衍射和原位拉曼光谱结果表明,CuO前驱体经过CO或H_(2)还原后被完全还原为金属态,并且在电化学还原条件下依旧呈现金属态,排除了催化剂价态对反应的影响.扫描电镜结果表明,两种催化剂的形貌没有明显区别,排除了催化剂形貌对反应的影响.高分辨透射电镜结果表明,COD-Cu表面因为CO的重构作用,产生相较于HOD-Cu更多的台阶位点,这与CO原位红外光谱结果一致(COD-Cu催化剂在2080 cm~(–1)波数处具有明显的台阶位点CO吸附峰).电化学CO_(2)还原活性测试结果表明,COD-Cu表现出更高的醇类产物选择性,相较于HOD-Cu,法拉第效率与部分电流密度均提升了5倍以上,醇类产物的法拉第效率达到40.5%,部分电流密度达到56.3 mAcm~(-2),产物中醇/烯烃比值为2.2.这表明台阶位点对调控反应路径促进醇类生成具有重要作用.结合原位衰减全反射表面增强傅里叶变换红外吸收光谱的阶跃电位和Ar气吹扫实验结果表明,COD-Cu因具有更多的台阶位点而表现出更高的催化CO_(2)到*CO反应活性,并有效促进后续的C–C偶联反应.通过热退火实验制备了具有不同台阶位点含量的COD-Cu催化剂,其台阶位点的含量与醇类产物的选择性保持良好的线性关系,进一步验证了台阶位点是促进醇类产物生成活性位点的结论.DFT结果也表明,台阶位点可以有效的提升关键中间体*CH_(2)CHO中C–O键强度,从而抑制C–O键断裂,促进醇类产物的生成.综上,本文提出了一种通过催化剂活性位点设计调控电催化CO_(2)还原反应路径的有效策略,为解析催化剂构效关系、明确活性位点提供参考.得益于催化科学的快速发展,具有高活性的CO_(2)还原电催化剂不断涌现,未来可在发展活性位点精细化调控方法、开发新型原位瞬态表征技术、创新催化剂失活机制原位研究方法等方面做出更多的努力.

镍催化杂芳烃的非天然戊烯基化及环状单萜化反应

萜类化合物,如半萜类和单萜类,是天然产物中种类最繁多、结构最多样的一类,广泛存在于植物和海洋生物中,在人类的日常生活中具有重要的应用价值.自然界中,二甲基烯丙基焦磷酸酯(DMAPP)和异戊烯基焦磷酸酯(IPP)在各种酶的作用下经过偶联、重排、环化以及异构化等反应合成萜类化合物.传统的人工方法大多依赖于过渡金属催化的异戊烯基以及反异戊烯基前体的反应,该反应不仅需要当量的金属试剂,且反应过程中也会产生当量的副产物,不符合绿色环保以及原子经济性原则.异戊二烯作为一种廉价易得的大宗化学品,其高附加值转化一直是学术界和工业界关注的焦点.但由于异戊二烯具有反应活性低以及区域选择性调控难的特点,氢芳基化产物最多可达到十四种异构体.此外,异戊二烯容易发生二聚、三聚以及调聚等反应,产生复杂产物.上述问题使得异戊二烯的高附加值转化具有很大挑战性.在前期关于异戊二烯氢官能团化以及手性二聚研究的基础上,本文提出了一种以异戊二烯为原料,通过接力催化策略,在杂芳环中引入非天然戊烯基和环状单萜骨架的方法.具体而言,使用廉价金属镍作为催化剂,小位阻的氮杂环卡宾作为配体,在当量碱的条件下,通过马氏加成得到异戊二烯4,3-氢杂芳基化产物,该策略具有广泛的底物普适性,较好的选择性和产率.机理研究表明,反应首先经过杂环化合物的C-H键氧化加成,再通过异戊二烯的配位以及迁移插入,最后通过还原消除获得目标产物.反应过程中没有当量副产物生成,符合原子经济性原则.而当体系中加入当量碱时,4,3-氢杂芳基化产物通过原位异构化获得了含有四取代烯烃的非天然半萜.机理研究表明,碱诱导的异构化和镍催化的分子内氢迁移的机理可能同时存在.进一步研究表明,通过控制不同位阻卡宾配体的添加过程,可以实现“一锅两步法”生成含有四取代烯烃的半萜衍生物和环状单萜衍生物;具体为先加入小位阻卡宾配体催化生成四取代烯烃,再加入大位阻卡宾配体以及杂环化合物,催化生成环状单萜衍生物.综上,本文不仅有助于大宗化学品异戊二烯的高效转化,而且发展的配体调控为半萜类化合物和单萜类化合物的发散性合成提供了新思路,具有潜在的应用价值.

Sputtered Stainless Steel on Silicon Photoanode for Stable Seawater Splitting in Photoelectrochemical Flow Cell

Photoelectrochemical(PEC)seawater splitting is a promising method for the direct utilization of solar energy and abundant seawater resources for hydrogen production.Photoelectrodes are susceptible to various ions in seawater and complicated competitive reactions,resulting in the failure of photoelectrodes.This paper proposes the design and fabrication of diff erent sputtered stainless steel(SS)fi lms deposited on silicon photoanodes,completely isolating the electrolytes and semiconductor substrate.Upon coupling with the PEC flow cell,the back-illuminated photoanode coated with 316 SS cocatalyst achieves stable operation for 70 h in natural seawater with a highly alkaline KOH(30 wt.%,7.64 mol/L)electrolyte due to the remarkable protection eff ect of the substrate from stainless steel,while the PEC seawater splitting system achieves a record hydrogen production rate of 600μmol/(h·cm^(2)).An appropriate Ni/Fe ratio in the SS ensures remarkable oxygen evolution activity,while chromic oxide ensures the effective anticorrosion effect by adjusting the microenvironment of the photoanodes.Moreover,fabricating PEC flow cells with photoanodes coated with SS cocatalysts are a viable strategy for PEC seawater splitting.

阿伐曲泊帕的合成

为了评估和开发阿伐曲泊帕的合成工艺,设计了汇聚型合成策略对其进行合成研究。分别以6-羟基烟酸为原料合成5,6-二氯烟酸;以异烟酸为原料合成4-哌啶甲酸乙酯;以无水哌嗪为原料合成1-环己基哌嗪,而后利用这些模块构建了关键中间体5-氯-6-[4-(乙氧基羰基)哌啶-1-基]吡啶-3-羧酸和4-(4-氯噻吩-2-基)-5-(4-环己基哌嗪-1-基)噻唑-2-胺,最后再进行缩合得到阿伐曲泊帕。整个工艺路线条件温和,可操作强,整体收率达到48.8%,此外,所得到的化合物及中间体都进行质谱、核磁等表征,其波谱数据与化合物结构吻合。

Angle estimation for bistatic MIMO radar with unknown mutual coupling based on three-way compressive sensing

The problem of angle estimation for bistatic multiple-input multiple-output radar in the present of unknown mutual coupling (MC) is investigated, and a three-way compressive sensing (TWCS) estimation algorithm is developed. To exploit the inherent multi-dimensional structure of received data, a trilinear tensor model is firstly formulated. Then the de-coupling operation is followed. Thereafter, the high-order singular value decomposition is applied to compress the high dimensional tensor to a much smaller one. The estimation of the compressed direction matrices are linked to the compressed trilinear model, and finally two over-complete dictionaries are constructed for angle estimation. Also, Cramer-Rao bounds for angle and MC estimation are derived. The proposed TWCS algorithm is effective from the perspective of estimation accuracy as well as the computational complexity, and it can achieve automatically paired angle estimation. Simulation results show that the proposed method has much better estimation accuracy than the existing algorithms in the low signal-to-noise ratio scenario, and its estimation performance is very close to the parallel factor analysis (PARAFAC) algorithm at the high SNR regions. © 2017 Beijing Institute of Aerospace Information.

Clinical characteristics and outcome of primary hepatic neuroendocrine tumors after comprehensive therapy

BACKGROUND Primary hepatic neuroendocrine tumors(PHNETs),a group of neuroendocrine neoplasms,are extremely rare.There are only few case reports about PHNETs in the literature.The lack of large samples and multicenter research results in poor diagnostic and therapeutic approaches.AIM To discuss the clinical characteristics,diagnosis,and treatment of PHNETs and risk factors related to survival.METHODS We retrospectively analyzed the clinical data,imaging features,immunohistochemistry data,and treatment efficacy of 40 patients who were pathologically diagnosed with PHNETs and admitted to The First Affiliated Hospital of Zhengzhou University from January 1,2014 to November 15,2019.Finally,survival analysis was performed to identify the risk factors for survival.RESULTS The main symptoms and signs included intermittent abdominal pain(19 patients,47.5%)and bloating(8 patients,20.0%).The positive rates of tested tumor markers were recorded as follows:Carbohydrate antigen 19-9(CA19-9)(6 patients,15.0%),CA72-4(3 patients,7.5%),carcinoembryonic antigen(7 patients,17.5%),and alpha-fetoprotein(6 patients,15.0%).Immunohistochemical staining results showed positivity for Syn in 38(97.4%)of 39 patients,for chromogranin A in 17(65.4%)of 26 patients,for CD56 in 35(94.6%)of 37 patients,for AE1/AE3 in 28(87.5%)of 32 patients,and for Ki-67 in all 40(100.0%)patients.The overall survival rate was significantly related to the tumor grade,AE1/AE3,and Ki-67.tumor number,tumor size,metastasis,and treatment)and overall survival.CONCLUSION Higher grade,negative AE1/AE3,and higher Ki-67 are associated with a worse survival rate.Kinds of treatment and other parameters have no significant influence on overall survival.

Dendritic branching patterns in platforms of complex Ni-based single crystal castings

Dendritic branching patterns at variable cross-sections in Ni-based single crystal(SX) castings of different generations were investigated using optical microscope(OM), electro probe microanalyzer(EPMA),differential scanning calorimeter(DSC), Thermo-Cal software and Pro-CAST software. Results show that the dendritic branching patterns are similar in outward platform in SXs of different generations. That is, the primary dendrites(PDs) are introduced into the platform by developing a series of secondary dendrites(SDs) to occupy the bottom of the platform, and the ternary dendrites(TDs) originating from these SDs grow upward to fill up the platform. With the SX generation increasing, the undercooling of melts in the inward platform increases significantly due to the increasing alloying elements and the segregation in the directional solidification(DS)process, and the growth velocity of the dendrite tip increases according to the dynamic model of dendrite growth,which is beneficial for the high-order dendrite development. The stronger dendritic branching ability is shown in the inward platform of the higher generation Ni-based SX.

Tailoring Oxygen Vacancy on Co3O4 Nanosheets with High Surface Area for Oxygen Evolution Reaction

Electrochemical water splitting requires efficient water oxidation catalysts to accelerate the sluggish kinetics of water oxidation reaction. Here, we designed an efficient Co304 electrocatalyst using a pyrolysis strategy for oxygen evolution reaction （OER）. Morphological characterization confirmed the ultra-thin structure of nanosheet. Further, the existence of oxygen vacancies was obviously evidenced by the X-ray photoelectron spectroscopy and elec- tron spin resonance spectroscopy. The increased surface area of Co3O4 ensures more exposed sites, whereas generated oxygen vacancies on Co3O4 surface create more active defects. The two scenarios were beneficial for accelerating the OER across the interface between the anode and electrolyte. As expected, the optimized Co3O4 nanosheets can catalyze the OER eftciently with a low overpotential of 310 mV at current density of 10 mA/cm2 and remarkable long-term stability in 1.0 mol/L KOH.

CLASSIFICATION OF SKIN AUTOFLUORESCENCE SPECTRUM USING SUPPORT VECTOR MACHINE IN TYPE 2 DIABETES SCREENING

Advanced glycation end products(AGEs)are a complex and heterogencous group of compounds that have been implicated in diabetes related complfcations.Sk in autofluorescence was recently introduced as an altemative tool for skin AGEs accumulation assessment in diabetes.Sucossful optical diagnosis of diabetes requires a rapid and accurate classification algorithm.In order to improve the performance of noninvasive and optical diagnosis of type 2 diabetes,support vector machines(SVM)algorithm was implemented for the clasification of skin autofluorescence from diabetics and control subjects.Cross-validation and grid optimization methods were employed to calculate the optimal parameters that ma ximize classification accuracy.Classification model was set up according to the training set and then veri fied by the testing set.The results show that radical basis fiunction is the best choice in the four common kernels in SVM.Moreover,a diagnostic accuracy of 82.61%,a sensitivity of 69.57%,and a specificity of 95.65%for discriminating diabetics from control subjects were achieved using a mixed kemel function,which is based on liner kernel function and radical basis function.In comparison with fasting plasma glucose and HbAue test,the clasifcation method of skin autofuorescence spectrum based on SVM shows great potential in screening of diabetes.

An Airborne Radar Clutter Tracking Algorithm Based on Multifractal and Fuzzy C-Mean Cluster

For an airborne Iookdown radar, clutter power often changes dynamically about 80 dB with wide distributions as the platform moves. Therefore, clutter tracking techniques are required to guide the selection of const false alarm rate （CFAR） schemes. In this work, clutter tracking is done in image domain and an algorithm combining multifractal and fuzzy C-mean （FCM） cluster is proposed. The clutter with large dynamic distributions in power density is converted to steady distributions of multifractal exponents by the multifractal transformation with the optimum moment. Then, later, the main lobe and side lobe are tracked from the multifractal exponents by FCM clustering method.

Catalytic C2 prenylation of unprotected indoles:Late‐stage diversification of peptides and two‐step total synthesis of tryprostatin B

C2 prenylated indoles are widespread in a variety of bioactive natural alkaloids.Therefore,theselective installation of prenyl group at C2 position of NH indoles is of great significance.However,the known protocols generally require a multi‐step procedure and stoichiometric promoters.Hereinwe develop a one‐step C2 prenylation of NH indole with cheap tert‐prenyl alcohol enabled by acidcatalysis.Salient features include good regioselectivity,step‐and atom‐economy,broad substratescope,and simple catalytic system.The mechanistic investigations demonstrate that both C2prenylation and C3 prenylation/migration pathways are engaged in the reaction.Notably,this practicalstrategy can be applied to the late‐stage diversification of tryptophan‐based peptides and concisesynthesis of tryprostatin B.

A rare case of primary well-differentiated angiosarcoma of the right atrium

Primary cardiac angiosarcoma is rare in clinic.However,it is the most common malignant tumor in the heart,accounting for 15%-35%of all cardiac tumors.It is a very aggressive disease characterized by high rates of local recurrence and systemic metastases,and it is a poor prognosis.Echocardiography,computed tomography(CT)and magnetic resonance imaging(MRI)are important tools for diagnosing cardiac angiosarcoma and are valuable in guiding surgical resection and in monitoring treatment efficacy.

Arrayed Cobalt Phosphide Electrocatalyst Achieves Low Energy Consumption and Persistent H2 Liberation from Anodic Chemical Conversion

Electrochemical reduction of water to hydrogen(H2) offers a promising strategy for production of clean energy,but the design and optimization of electrochemical apparatus present challenges in terms of H2 recovery and energy consumption.Using cobalt phosphide nanoarrays(Co2 P/CoP NAs) as a charge mediator,we effectively separated the H2 and O2 evolution of alkaline water electrolysis in time,thereby achieving a membrane-free pathway for H2 purification.The hierarchical array structure and synergistic optimization of the electronic configuration of metallic Co2 P and metalloid CoP make the Co2 P/CoP NAs high-efficiency bifunctional electrocatalysts for both charge storage and hydrogen evolution.Theoretical investigations revealed that the introduction of Co2 P into CoP leads to a moderate hydrogen adsorption free energy and low water dissociation barrier,which are beneficial for boosting HER activity.Meanwhile,Co2 P/CoP NAs with high capacitance could maintain a cathodic H2 evolution time of 1500 s at 10 mA cm^(-2) driven by a low average voltage of 1.38 V.Alternatively,the energy stored in the mediator could be exhausted via coupling with the anodic oxidation of ammonia,whereby only 0.21 V was required to hold the current for 1188 s.This membrane-free architecture demonstrates the potential for developing hydrogen purification technology at low cost.

Schemes for synthesizing high-resolution range profile with extended OFDM-MIMO

Two novel schemes are proposed to synthesize high resolution range profile (HRRP) based on co-located multiple-input multiple-output (MIMO) system in the context of the joint radar and communication system. The difference between two schemes is the pattern of selecting pulses, which depends on the demand for the velocity information. The system, a type of frequency diverse array (FDA), takes full advantage of the phase-coded orthogonal frequency division multiplexing (OFDM) signal. Furthermore, the complete discrete form of the phase-coded OFDM echoes is utilized to derive the HRRP processing. The velocity estimation in the second scheme aims to eliminate velocity ambiguity, and high velocity can be retrieved exactly. Meanwhile, the imaging method is investigated with random frequency coding applied to an array. The desired performance of resolving velocity ambiguity and suppressing noise is shown by means of comparisons with previous work. The advantages in the radar imaging and the significance of the work are concluded in the end.

In situ thermoresponsive supramolecular assembly for switchable circularly polarized luminescence

The dynamic regulation of circularly polarized luminescence(CPL)holds profound significance in various fields,such as highlevel information storage and encryption.Here we developed a chiral amphiphilic molecule,CPSB-GLU-PEG350(CGP),composed of aggregation-induced emission(AIE)chromophores(Z)-4-(1-cyano-2-phenylvinyl)benzoic acid(CPSB),a chiral linker Glutamic acid and polyethylene glycol(PEG)thermoresponsive segments.Within the self-assembled supramolecular system formed by CGP,we have achieved in-situ temperature-responsive chiral structures,facilitating the thermal control switch of the CPL signal.Molecular dynamics simulations demonstrate the distinct behaviors of AIE and PEG units during the temperature-variable assembly process.Furthermore,by co-assembling achiral dye molecules with CGP,we have expanded the color range of the temperature-responsive CPL assembly system in situ and confirmed the occurrence of circularly polarizedF?rster resonance energy transfer(C-FRET)phenomenon in this process,which successfully enriched the strategies for in-situ CPL control in aqueous phases.In addition,the contactless radiative energy transfer of CPL can also be realized in this system,exhibiting more flexible temperature regulation of the CPL signal.This study provides a convenient and universal strategy for the construction of dynamically smart chiroptical materials.

Short term temporal variability of selected organophosphate esters among healthy adults living in the National Capital Region of Canada

Organophosphate esters(OPEs)are used primarily as flame-retardants and plasticizers.OPEs are commonly detected in various environmental matrices,food and drinking water,and their metabolites are frequently found and quantified in urine.Potential adverse impacts on human health,including carcinogenicity,neurotoxicity,developmental and reproductive toxicity have been well documented.Urinary concentration of OPE metabolites can vary in the same individual,depending on the sampling time,thus introducing significant uncertainty in exposure assessment.The current study focusses on the assessment of short term temporal variability in adult men and women residing in Canada's Capital Region.Fifteen OPE metabolites were analyzed in 562 daily urine samples,collected every three days for five weeks from 11 volunteers.Sample extraction procedure was performed on an automated SPE and extracts analyzed using UPLC-MS/MS.In spot urine samples as well as first morning void(FMV),the detection frequency was greater than 50%for bis(2-chloroethyl)hydrogen phosphate(BCEP),bis(1-chloro-2-propyl)phosphate(BCIPP),bis(1,3-dichloro-2-propyl)phosphate(BDCIPP),diphenyl phosphate(DPHP)and bis(2,4-ditert-butylphenyl)hydrogen phosphate(B2,4DtBPP).Significant difference was observed in males and females for BCEP and BCIPP.Intra-class correlation coefficient(ICC)for creatinine corrected data for the spot urine samples ranged from 0.37 to 0.69.Good reproducibility was observed for creatinine corrected DPHP and BCIPP in both spot urine and FMV samples.More variation was observed between study participants in the spot urine samples when compared to the FMV samples.However,when considering diurnal difference there was a considerable inter-day variation in the FMV samples compared to the spot samples.The strength of the study is that the participants belonged to the same geographical location and working in the same facility,hence spatial variability did not influence the outcome of the results.

Copy number variation of NAL23 causes narrow-leaf development in rice

Leaf shape is a key trait for plant architecture relating to photosynthesis and transpiration in plants(Lawson et al.,2020).Erect leaves with proper leaf length and width,particularly the upper three leaves in cereal crops,could significantly improve light absorption efficiency in canopy and ultimately increase crop yield(Jiao et al.,2010).Rice leaves initiate at the peripheral zone of shoot apical meristem,then develop along the proximal-distal,adaxial-abaxial,and mediallateral axes to form a flat symmetric architecture(Du et al.,2018).