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We present a fully tunable multistage narrowband optical pole-zero notch filter that is fabricated in a silicon complementary metal oxide semiconductor (CMOS) foundry. The filter allows for the reconfigurable and independent tuning of the center frequency, null depth, and bandwidth for one or more notches simultaneously. It is constructed using a Mach-Zehnder interferometer (MZI) with cascaded tunable all-pass filter (APF) ring resonators in its arms. Measured filter nulling response exhibits ultranarrow notch 3 dB BW of 0.6350 GHz, and nulling depth of 33 dB. This filter is compact and integrated in an area of 1.75 mm 2. Using this device, a novel method to cancel undesired bands of 3 dB bandwidth of 910 MHz in microwave-photonic systems is demonstrated. The ultranarrow filter response properties have been realized based on our developed low-propagation loss silicon channel waveguide and tunable ring-resonator designs. Experimentally, they yielded a loss of 0.25 dB/cm and 0.18 dB/round trip, respectively.

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All of the equilibrium data on the ammonia synthesis reaction, which cover an extreme temperature range of from 325' to 952'C and an extreme pressure range (at some temperatures) of from 10 to 1000 atmospheres, are correlated with the compressibility and heat capacity data on the pure reacting gases by means of a rational and relatively simple equation for the mass action function E". In this equation the effect of temperature and of pressure on X"are separated, the relation for the temperature eRect being exact, but certain approximations being introduced for the sake of simplicity into the relation for the pressure eRect.All of the data on the ammonia synthesis equilibrium are represented within the experImental accuracy by the use of only two adjustable constants.