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Objective: To investigate the effectiveness of sterilization of different weighty surgical instrument packages and their effect on packing experience such as operators’ working satisfaction and acceptance. Methods: Orthopedic surgical instruments of the same material were grouped into 8 different weight groups: 7 kg, 9 kg, 11 kg, 13 kg, 15 kg, 17 kg, 19 kg, 21 kg. Class 4 multi-variable CI, Class 5 integrating indicator and biological indicators were put at the least favorable position for sterilization within the packages and the monitoring results were interpreted after normal sterilization cycle to assess the sterilization performance. The operators packed the instrument with the same packaging materials, and then investigators evaluated the acceptability of the instrument package weights to the operators. Results: Instrument packages weighing between 7 kg and 11 kg produced acceptable results in chemical and biological monitoring using the normal sterilization procedure. Package weight exceeding 11 kg indicated uneven color change in Class 4 multi-variable CI, while Class 5 integrating indicator and biological monitoring produced acceptable results only with some wet packs. Instrument packages exceeding 11 kg made packing difficult for operators and resulted in low satisfaction. Conclusion: Package weights not exceeding 11 kg were associated with effective sterilization in normal sterilization procedures, and with good operator satisfaction.

Three kinds of electron-blocking layer(EBL) AlGaN based LED were compared numerically.They are conventional AlGaN EBL,AlGaN-GaN-AlGaN(AGA) and gradual Al composition AlGaN-GaN-AlGaN(GAGA) EBL.Their porfermance were analyzed involved carrier concentration in the active region,energy band diagram,electrostatic field and internal quantum efficiency(IQE).The results indicate that the LED with an GAGA EBL exhibits a better hole injection efficiency,a more peaceable efficiency droop,a lower electron leakage,and a smaller electrostatic field than the LED with a conventional AlGaN EBL or with an AGA EBL.

In order to realize preferable white light-emitting diodes with high color rendering index and optimized luminous efficiency,white InGaN/GaN multi-quantum-well dual-wavelength light-emitting diodes(LEDs) were grown on(0001)-oriented sapphire substrates by metal-organic chemical vapor deposition(MOCVD).Photoluminescence and electroluminescence properties of dual-wavelength LEDs with different In content were also studied.The experimental results indicated that In component plays a critical role on stability for electroluminescence spectrum and luminous efficiency of the dual-wavelength LED structures.In addition,YAG∶Ce phosphor-converted white light emission with high color rendering index was achieved using dual-blue emitting active regions.

The influence of Si doping on the photoluminescence (PL) properties of (Al"0"."3Ga"0"."7)"0"."5In"0"."5P/Ga"0"."5In"0"."5P multiple-quantum-wells (MQWs) was studied. For the samples without p-type layers, the PL peak wavelength from (Al"0"."3Ga"0"."7)"0"."5In"0"."5P/Ga"0"."5In"0"."5P MQWs did not vary when Si was doped in MQWs, the PL peak intensity did not change obviously and the PL FWHM broadened. We consider that Si doping results in worse interface quality of (Al"0"."3Ga"0"."7)"0"."5In"0"."5P/Ga"0"."5In"0"."5P MQWs. However, for the full light-emitting diode (LED) structure samples, the PL intensity of MQWs obviously increased when Si was doped in MQWs. The PL intensity from MQWs with Si-doped barriers was about 13 times stronger than that of undoped MQWs. The PL intensity from MQWs with Si-doped barriers and wells was strong as 28 times as that of undoped MQWs. The reasons are discussed.

AlGaInP/GaInP multiple quantum well structures were grown by low-pressure MOCVD on n-GaAs substrates. The influence of Si-doping to the characteristics of AlGaInP/GaInP multiple quantum wells was studied. The PL intensity from MQW with Si-doped barriers is about 13 times stronger than that of undoped MQW. The PL intensity from MQW with Si-doped barriers and wells is strong as 28 times as that of undoped MQW.

The characteristics of nitride-based blue light-emitting diodes (LEDs) with AlGaN composition-graded barriers are analyzed numerically. The carrier concentrations in the quantum wells (QWs), the energy band diagrams, the electrostatic fields, and the light output power are investigated by APSYS software. The simulation results show that the LED with AlGaN composition-graded barriers has a better performance than its AlGaN/InGaN counterpart owing to the increase of hole injection and the enhancement of electron confinement. The simulation results also suggest that the output power is enhanced significantly and the efficiency droop is markedly improved when the AlGaN barriers are replaced by AlGaN composition-graded barriers.