The aim of this work is to study the heterogeneous oxidative degradation of ofloxacin antibiotic using a composite material prepared from sodium alginate and cyclohexane dinitrilo tetraacetic acid（CDTA）. The charact...The aim of this work is to study the heterogeneous oxidative degradation of ofloxacin antibiotic using a composite material prepared from sodium alginate and cyclohexane dinitrilo tetraacetic acid（CDTA）. The characterization tests indicated the successful incorporation of metal chelator and iron. It was also demonstrated that the synthesized beads are mesoporous. The influence of several experimental parameters（i.e.： H2O2 dose,working temperature, beads loading and initial drug concentration） on the process performances was evaluated. The reaction temperature significantly affects the drug conversion efficiency. It was also observed that the synthesized material was efficient toward the target antibiotic degradation in the presence of small quantities of hydrogen peroxide. Under optimum conditions（0.05 g of granules, initial drug concentration = 10 mg/L,25 μL of 10 mmol/L H2O2）, conducted in a batch reaction, 94% degradation of ofloxacin was reached. The results also indicate that the composite material showed a reasonable stability;a relatively low decrease of activity after four successive runs（only 9%） and a negligible iron leaching（0.8%） have been observed. The synthesized composite material offered interesting advantages in terms of simplicity, good stability, ease of recovery from the liquid medium after use and its efficiency in the presence of low quantities of oxidant. It constitutes a good candidate in the water treatment area.展开更多
A switched capacitor biquad filter using current differencing transconductance amplifier (CDTA) is presented in this paper. The proposed circuit employs only one CDTA, two virtually grounded capacitors and one switche...A switched capacitor biquad filter using current differencing transconductance amplifier (CDTA) is presented in this paper. The proposed circuit employs only one CDTA, two virtually grounded capacitors and one switched capacitor. It is a resistorless circuit, so it is beneficial to IC implementation in terms of space consideration. The proposed circuit is a second order single input multiple output (SIMO) current-mode filter. This filter can simultaneously realize all basic filter functions high pass, low pass and band pass responses without any component-matching conditions. All the active and passive sensitivities are low. The natural angular frequency (ω0) and quality factor (Q) of proposed filter can be electronically controlled. Owing to current mode operation it consumes less power. PSPICE simulation results are used to verify the theoretical analysis.展开更多
The title compound CuC14H22N2O9 was crystallized in the monoclinicspace group P21/n(# 14), with a= 9. 032(1), b= 13. 044(6), c= 14. 779(7) A, β=101. 50(3)°, V= 1706. 9(1) A 3, Dc= 1.54 g/cm3, Z=4, Mr= 425. 54, ...The title compound CuC14H22N2O9 was crystallized in the monoclinicspace group P21/n(# 14), with a= 9. 032(1), b= 13. 044(6), c= 14. 779(7) A, β=101. 50(3)°, V= 1706. 9(1) A 3, Dc= 1.54 g/cm3, Z=4, Mr= 425. 54, λ(Mo-Ka) =0. 71069A, μ= 13. 3 cm-1, F(000) = 780, the final R= 0. 058 and Rw= 0. 083 for2322 observable reflections with I> 3δ(I). The Cu atom is coordinated by two Natoms and three O atoms from cdta (cdta = trans-cyclohexane-1, 2-diamine-N, N,N’,N’-tetra-acetate) which acts as pentadentate ligand.展开更多
This paper presents a floating resistor employing CIDITA (current inverting differential input transconductance amplifier). The proposed floating resistor is based on CMOS technology of 0.18 μm. For the realization o...This paper presents a floating resistor employing CIDITA (current inverting differential input transconductance amplifier). The proposed floating resistor is based on CMOS technology of 0.18 μm. For the realization of this floating inductor, two CIDITA have been cascaded together, no other passive elements are used, giving advantage of reduced chip area and hence reduced losses. The given circuit topology has an advantage of realizing both positive and negative resistors. This paper presents a simple circuitry of floating resistor in which the value of resistance can be tuned by adjusting the gate voltage of MOSFET. The PSpice simulation result shows constant resistance of 1.6 K<span style="white-space:nowrap;">Ω for frequency bandwidth of 1 Hz to 1 MHz, with supply voltage of ±1.25 volts.展开更多
提出了一种具有Z端复制输出、跨导可由电压调节的电流差分跨导放大器(MO-VCCDTA)。该电路采用低压高性能电流镜作为电流输入级,降低了消耗的电压余度、输入阻抗与传输误差;利用MOS管的线性组合,实现了可由电压控制跨导的跨导放大级。采...提出了一种具有Z端复制输出、跨导可由电压调节的电流差分跨导放大器(MO-VCCDTA)。该电路采用低压高性能电流镜作为电流输入级,降低了消耗的电压余度、输入阻抗与传输误差;利用MOS管的线性组合,实现了可由电压控制跨导的跨导放大级。采用SMIC 0.18μm CMOS工艺进行仿真,结果表明:在±0.9 V电源电压下,电路的线性输入范围为-100μA^100μA,输入电阻约为10Ω;跨导值可在0.34 m S^1.56 m S内线性变化,iz/ii、ix/ii的-3 d B带宽分别为131 MHz、88 MHz;电路总功耗为2.8 m W。最后,仅采用两个该模块和两个接地电容得到了电流模式通用二阶滤波器。展开更多
基金supported by the Tunisian Ministry of Higher Education and Scientific Research
文摘The aim of this work is to study the heterogeneous oxidative degradation of ofloxacin antibiotic using a composite material prepared from sodium alginate and cyclohexane dinitrilo tetraacetic acid（CDTA）. The characterization tests indicated the successful incorporation of metal chelator and iron. It was also demonstrated that the synthesized beads are mesoporous. The influence of several experimental parameters（i.e.： H2O2 dose,working temperature, beads loading and initial drug concentration） on the process performances was evaluated. The reaction temperature significantly affects the drug conversion efficiency. It was also observed that the synthesized material was efficient toward the target antibiotic degradation in the presence of small quantities of hydrogen peroxide. Under optimum conditions（0.05 g of granules, initial drug concentration = 10 mg/L,25 μL of 10 mmol/L H2O2）, conducted in a batch reaction, 94% degradation of ofloxacin was reached. The results also indicate that the composite material showed a reasonable stability;a relatively low decrease of activity after four successive runs（only 9%） and a negligible iron leaching（0.8%） have been observed. The synthesized composite material offered interesting advantages in terms of simplicity, good stability, ease of recovery from the liquid medium after use and its efficiency in the presence of low quantities of oxidant. It constitutes a good candidate in the water treatment area.
文摘A switched capacitor biquad filter using current differencing transconductance amplifier (CDTA) is presented in this paper. The proposed circuit employs only one CDTA, two virtually grounded capacitors and one switched capacitor. It is a resistorless circuit, so it is beneficial to IC implementation in terms of space consideration. The proposed circuit is a second order single input multiple output (SIMO) current-mode filter. This filter can simultaneously realize all basic filter functions high pass, low pass and band pass responses without any component-matching conditions. All the active and passive sensitivities are low. The natural angular frequency (ω0) and quality factor (Q) of proposed filter can be electronically controlled. Owing to current mode operation it consumes less power. PSPICE simulation results are used to verify the theoretical analysis.
文摘The title compound CuC14H22N2O9 was crystallized in the monoclinicspace group P21/n(# 14), with a= 9. 032(1), b= 13. 044(6), c= 14. 779(7) A, β=101. 50(3)°, V= 1706. 9(1) A 3, Dc= 1.54 g/cm3, Z=4, Mr= 425. 54, λ(Mo-Ka) =0. 71069A, μ= 13. 3 cm-1, F(000) = 780, the final R= 0. 058 and Rw= 0. 083 for2322 observable reflections with I> 3δ(I). The Cu atom is coordinated by two Natoms and three O atoms from cdta (cdta = trans-cyclohexane-1, 2-diamine-N, N,N’,N’-tetra-acetate) which acts as pentadentate ligand.
文摘This paper presents a floating resistor employing CIDITA (current inverting differential input transconductance amplifier). The proposed floating resistor is based on CMOS technology of 0.18 μm. For the realization of this floating inductor, two CIDITA have been cascaded together, no other passive elements are used, giving advantage of reduced chip area and hence reduced losses. The given circuit topology has an advantage of realizing both positive and negative resistors. This paper presents a simple circuitry of floating resistor in which the value of resistance can be tuned by adjusting the gate voltage of MOSFET. The PSpice simulation result shows constant resistance of 1.6 K<span style="white-space:nowrap;">Ω for frequency bandwidth of 1 Hz to 1 MHz, with supply voltage of ±1.25 volts.
文摘提出了一种具有Z端复制输出、跨导可由电压调节的电流差分跨导放大器(MO-VCCDTA)。该电路采用低压高性能电流镜作为电流输入级,降低了消耗的电压余度、输入阻抗与传输误差;利用MOS管的线性组合,实现了可由电压控制跨导的跨导放大级。采用SMIC 0.18μm CMOS工艺进行仿真,结果表明:在±0.9 V电源电压下,电路的线性输入范围为-100μA^100μA,输入电阻约为10Ω;跨导值可在0.34 m S^1.56 m S内线性变化,iz/ii、ix/ii的-3 d B带宽分别为131 MHz、88 MHz;电路总功耗为2.8 m W。最后,仅采用两个该模块和两个接地电容得到了电流模式通用二阶滤波器。
