Cook linguine in 3 quarts boiling water until done but firm to the bite. Set aside and keep warm. Meanwhile, in a 10" skillet, saute onion and celery 2 minutes in olive oil. Add sweet red pepper, broccoli and 1/2 cup of the chicken broth. Cover and cook 2 minutes. Add cornstarch to remaining cup chicken broth and set aside. Stir in shrimp, garlic, green onions, reserved chicken broth and cornstarch, white wine, lemon juice and pepper into vegetables. Cover and cook 2 to 3 minutes or until shrimp has turned pink and the sauce has thickened. Serve immediately over cooked noodles.