With the wide application of electromagnetic wave,a high performance electromagnetic shielding material is urgently needed to solve the harm caused by electromagnetic wave.Complete cross-linking strategy is adopted in...With the wide application of electromagnetic wave,a high performance electromagnetic shielding material is urgently needed to solve the harm caused by electromagnetic wave.Complete cross-linking strategy is adopted in this paper.Polyacrylamide(PAM)was synthesized by in-situ polymerization of acrylamide(AM)monomer.The obtained PAM was blended with polyethylene glycol(PEG)to prepare PAM/PEG hydrogels and form rigid support structures.Subsequently,the modified carbon nanotubes(S-CNTs)were incorpor-ated into sodium alginate(SA)and PAM/PEG.Finally,Na+was used to trigger SA self-assembly,which significantly improved the mechanical properties and electrical conductivity of the hydrogels,and prepared PAM/PEG/SA/S-CNTs-Na hydrogels with high tough-ness and strong electromagnetic interference(EMI)shielding efficiency(SE).The results showed that the compressive strength of PAM/PEG/SA/S-CNTs-Na hydrogel was 19.05 MPa,which was 7.69%higher than that of PAM/PEG hydrogel(17.69 MPa).More en-couraging,the average EMI SE of PAM/PEG/SA/S-CNTs-Na hydrogels at a thickness of only 3 mm and a CNTs content of 16.53wt%was 32.92 dB,which is 113.21%higher than that of PAM/PEG hydrogels(15.44 dB).展开更多
The adsorption of phosphate was conducted by the complex of chitosan/polyacrylamide/ferric(CS/PAM/Fe(Ⅲ))prepared.The SEM images and XPS spectra confirmed the successful adsorption of phosphate.The adsorption process ...The adsorption of phosphate was conducted by the complex of chitosan/polyacrylamide/ferric(CS/PAM/Fe(Ⅲ))prepared.The SEM images and XPS spectra confirmed the successful adsorption of phosphate.The adsorption process was studied by varying the influencing aspects like pH,co-existing ions,contact time,and initial phosphate concentration.The experimental results indicate that the adsorptive capacity decreases with the increase of pH.However,it is commendable that there is still a adsorption capacity of more than 5 mg/g when the pH is 8-11.The adsorption kinetics can be accurately described by the pseudo-second-order model and is controlled by both chemisorption and surface diffusion.The adsorption process is a single layer adsorption.This paper proposed that the adsorption mechanism of CS/PAM/Fe(Ⅲ)complex is the joint action of electrostatic attraction and ligand exchange.展开更多
提出了一种适用于超短距离(Very Short Reach,VSR)信道、面向112 Gb/s PAM4(Pulse Amplitude Modulation 4)接收机的自适应均衡设计方案。在该方案中,接收机前端利用3个连续时间线性均衡器(Continuous Time Linear Equalizer,CTLE)对信...提出了一种适用于超短距离(Very Short Reach,VSR)信道、面向112 Gb/s PAM4(Pulse Amplitude Modulation 4)接收机的自适应均衡设计方案。在该方案中,接收机前端利用3个连续时间线性均衡器(Continuous Time Linear Equalizer,CTLE)对信号分别在高频、中频和低频进行补偿,可变增益放大器(Variable Gain Amplifier,VGA)和饱和放大器(Saturation Amplifier,SatAmp)则用于对信号幅值的缩放。除了3个数据采样器外,引入4个辅助采样器用于进一步改善阈值自适应算法性能。同时,采用符号最小均方算法,利用接收端数据采样器和辅助采样器之间的偏移推动辅助参考电压收敛到信号星座电平,从而确保PAM4接收信号的眼图在垂直方向上3个眼睛具有相等的间隔和恒定的信噪比(Signal-to-Noise Ratio,SNR)。仿真结果表明,所提出的112 Gb/s PAM4接收机能够在损耗为15 dB的信道上实现小于10~(-12)的误码率,并且具有良好的眼图性能,其最差眼高为75 mV,眼宽为0.34 UI(Unit Interval),与传统方案相比具有显著的性能提升。展开更多
基金supported by the National Natural Science Foundation of China(No.52163001)the Guizhou Provincial Science and Technology Program Project Grant,China(Qiankehe Platform Talents-CXTD[2021]005,Qiankehe Platform Talents-GCC[2022]010-1,Qiankehe Fuqi[2023]001,Qiankehe Platform Talents-GCC[2023]035,and Qiankehe Platform Talents-CXTD[2023]003)+3 种基金the Guizhou Minzu University Research Platform Grant,China(No.GZMUGCZX[2021]01)the Central Guided Local Science and Technology Development Funds Project,China(Qiankehe Zhong Yindi[2023]035)the Green Chemistry and Resource Environment Innovation Team of Guizhou Higher Education Institutions,China(Guizhou Education and Technology[2022]No.13)the Doctor Startup Fund of Guizhou Minzu University,China(No.GZMUZK[2024]QD77).
文摘With the wide application of electromagnetic wave,a high performance electromagnetic shielding material is urgently needed to solve the harm caused by electromagnetic wave.Complete cross-linking strategy is adopted in this paper.Polyacrylamide(PAM)was synthesized by in-situ polymerization of acrylamide(AM)monomer.The obtained PAM was blended with polyethylene glycol(PEG)to prepare PAM/PEG hydrogels and form rigid support structures.Subsequently,the modified carbon nanotubes(S-CNTs)were incorpor-ated into sodium alginate(SA)and PAM/PEG.Finally,Na+was used to trigger SA self-assembly,which significantly improved the mechanical properties and electrical conductivity of the hydrogels,and prepared PAM/PEG/SA/S-CNTs-Na hydrogels with high tough-ness and strong electromagnetic interference(EMI)shielding efficiency(SE).The results showed that the compressive strength of PAM/PEG/SA/S-CNTs-Na hydrogel was 19.05 MPa,which was 7.69%higher than that of PAM/PEG hydrogel(17.69 MPa).More en-couraging,the average EMI SE of PAM/PEG/SA/S-CNTs-Na hydrogels at a thickness of only 3 mm and a CNTs content of 16.53wt%was 32.92 dB,which is 113.21%higher than that of PAM/PEG hydrogels(15.44 dB).
基金Funded by the Provincial Natural Science Foundation for Universities of AnhuiChina(No.KJ2021A0624)+1 种基金the Director's Fund of Anhui Province Advanced Building Materials International Research Center(No.JZCL2207ZR)the Anhui Jianzhu University Talent Introduction and Doctoral Start-up Fund(No.2023QDZ23)。
文摘The adsorption of phosphate was conducted by the complex of chitosan/polyacrylamide/ferric(CS/PAM/Fe(Ⅲ))prepared.The SEM images and XPS spectra confirmed the successful adsorption of phosphate.The adsorption process was studied by varying the influencing aspects like pH,co-existing ions,contact time,and initial phosphate concentration.The experimental results indicate that the adsorptive capacity decreases with the increase of pH.However,it is commendable that there is still a adsorption capacity of more than 5 mg/g when the pH is 8-11.The adsorption kinetics can be accurately described by the pseudo-second-order model and is controlled by both chemisorption and surface diffusion.The adsorption process is a single layer adsorption.This paper proposed that the adsorption mechanism of CS/PAM/Fe(Ⅲ)complex is the joint action of electrostatic attraction and ligand exchange.
